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1. [Spring-Framework] 31. AOP(Aspect-Oriented-Programming) 관점지향 프로그래밍 (Java셋팅) (1)

https://yyman.tistory.com/1447

패키지 경로: com.local.example.aop

package com.local.example.aop;

import org.springframework.context.annotation.ComponentScan;

import org.springframework.context.annotation.Configuration;

import org.springframework.context.annotation.EnableAspectJAutoProxy;

@Configuration

@ComponentScan(basePackages = {"com.local.example.aop"})

//@ComponentScan(basePackages = {"com.local.example.beans", "com.local.example.advisor"})

@EnableAspectJAutoProxy

public class RootConfig {

}

패키지 경로: com.local.example.aop

package com.local.example.aop;

import org.springframework.stereotype.Service;

@Service("cal")

public class Calculator {

private long x;

private long y;

private long z;

public Calculator() {

this.x = 1;

this.y = 2;

this.z = 3;

}

public Calculator(long x, long y, long z) {

this.x = x;

this.y = y;

this.z = z;

}

// 작업 원본(A 프로그래머 작성함)

public long sum() {

long result = x + y + z;

System.out.println("비즈니스 로직");

// long d = result / 0; - 일부러 만든 코드(After Throws 보여줄려고)

return result;

}

}

(참고)

주석 친 부분을 주석 풀면, After Throws를 정의한 경우라면 메시지가 출력되는 것을 볼 수 있다.

패키지 경로: com.local.example.aop

package com.local.example.aop;

import org.aspectj.lang.JoinPoint;

import org.aspectj.lang.ProceedingJoinPoint;

import org.aspectj.lang.annotation.After;

import org.aspectj.lang.annotation.AfterThrowing;

import org.aspectj.lang.annotation.Around;

import org.aspectj.lang.annotation.Aspect;

import org.aspectj.lang.annotation.Before;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.stereotype.Service;

// 관점, 서비스

@Aspect

@Service

// 콤포넌트 사용하지 말것

public class Log {

Logger logger =  LoggerFactory.getLogger(Log.class);

// 섞어적어놓아도 순서를 찾아서 강제 인식함.

// 2단계 - 전 단계 시야)

@Before("execution(* com.local.example.aop.Calculator.*(..))")

// @Before("execution(public void sum())")

// 반환값 없어도 무방

    public void logBefore() { 

logger.info("전 단계 관점 - 구현(Before)");

    }

// 1단계 - Before보다 전 단계 실행

    // Calculator 클래스의 모든 메서드

// 무조건 반환값이 지정되어야 함. (ProceedingJoinPoint에 대한 Object 반환값 필수 정의되어야 함)

// @Around 이 친구만 Pjp가 있어야 함.

    @Around("execution(* com.local.example.aop.Calculator.*(..))")

    /*@Around("execution(* com.example.demo.controller..*.*(..))")*/

    /*@Around("execution(* com.example.demo..*.*(..))")*/

    public Object logAround(ProceedingJoinPoint pjp) throws Throwable { 

logger.info("Around 단계 - 구현(Around)");

Object result = pjp.proceed();

return result;

    }

    // 3단계는 (중간) - 임의로 지정해줄 수 있는 것이 아님.

// 4단계: After advice

//@After("execution(* method1())")  -- method1 함수만 실행 

    // (이렇게 하면 안 됨. sum()을 콜하니깐)

    // @After("execution(* method1())")

    @After("execution(* sum())")

public void afterMethod() {

    logger.info( "after Method 호출" );

}

    // 5단계: 맨 마지막 단계

// after-throwing advice /// 오류가 발생할 때 호출함(무조건 보여지는 영역은 아님

    // 쉽게 비유하면, try to catch finally에서 catch 단계로 보면 됨.

    // 오류도 출력되고 after Throwing 로그 메시지도 출력된다.

    // 이 화면을 보려면, 오류나는 코드에 try to catch finally를 적용하면 안 됨.

    // 원본 비즈니스 로직 코드는 그대로 둘 것

    @AfterThrowing(

        pointcut = "execution(* com.local.example.aop.Calculator.sum(..))", 

        throwing = "ex"

    )

public void afterThrowingMethod(JoinPoint joinPoint, Throwable ex) {

logger.info( "after Throwing 호출" + ex.getMessage());

}

}

[비고]

- @Around 정의만 Object로 반환값을 잡아줘야 한다. (선택이 아니라 필수이다. 이렇게 안 하면 오류 출력에도 반환값 잡아달라고 나온다.)

패키지 경로: com.local.example

package com.local.example;

import java.text.DateFormat;

import java.util.Date;

import java.util.Locale;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import org.springframework.context.annotation.EnableAspectJAutoProxy;

import org.springframework.stereotype.Controller;

import org.springframework.ui.Model;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import com.local.example.aop.Calculator;

import com.local.example.aop.RootConfig;

/**

 * Handles requests for the application home page.

 */

@EnableAspectJAutoProxy

@Controller

public class HomeController {

private static final Logger logger = LoggerFactory.getLogger(HomeController.class);

/**

* Simply selects the home view to render by returning its name.

*/

@RequestMapping(value = "/", method = RequestMethod.GET)

public String home(Locale locale, Model model) {

logger.info("Welcome home! The client locale is {}.", locale);

Date date = new Date();

DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG, DateFormat.LONG, locale);

String formattedDate = dateFormat.format(date);

// Java 방식 - AOP

AnnotationConfigApplicationContext context = 

new AnnotationConfigApplicationContext(RootConfig.class);

// 1. 이전 방식

// Calculator cal = new Calculator(1, 2, 3);

// 2. Aspect 적용

// 소문자로 입력(Calculator -> calculator로)

Calculator cal = (Calculator)context.getBean("cal", Calculator.class);

System.out.printf("result of sum: %d", cal.sum());

model.addAttribute("serverTime", formattedDate );

return "home";

}

}

비고(생각하기): 지금 작성한 Calculator 클래스만 사용가능한가요?

아니다. aop 작업을 거친 클래스들은 자유롭게 사용가능하다.

RootConfig.java 환경설정 확인과 새로 사용할 클래스에 정의 명세, Log 파일 하나 더 만들기 등을 해줘야 한다.

해당 작업은 Spring Framework에서만 가능한 작업이다.

IDE: Spring Tool-Suite 4-4.7.2 Release(2020-08월)
Library: 

- Spring Framework 5.2.9.RELEASE (2020-09-15)

- Java Version: 14

- AspectJ: 1.9.6 (2020-07-22)

- AspectJ Weaver: 1.9.6 (2020-07-22)

- javax.servlet-api 4.0.1 (2018-04-20)

(순정 상태로 셋팅하였음.)

Project: Spring Legacy Project로 생성할 것

-> 안 보이는 사람들은 Help->Eclipse Marketplace -> STS 검색 후 "Spring Tools 3 Add-On for Spring Tools 4 3.9.14.RELEASE" 설치할 것

그림 1. STS-Addon (Eclipse Marketplace)

Type of Classes username new Proxy.newProxyInstance(Classes.class.getClassLoader(), new Class[] { classes.class } , 

new InvocationHandler(){

          public Object invoke(Object proxy, Method method, Object args[] throws Throwable{

                  // 전단계 호출

                  Object result = method.invoke(sum, args);

                  // 후단계 호출

         }

     }

};

Spring AOP에서는 5단계로 확장되었다.

전단계:    {Around 단계, Before 단계}, 

핵심로직:         핵심 로직(중간)

후단계:    {after Method 호출, AfterThrowing(선택 - 예외 처리 발생 때만)}

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/maven-v4_0_0.xsd">

<modelVersion>4.0.0</modelVersion>

<groupId>com.local</groupId>

<artifactId>example</artifactId>

<name>springAOP-javaConfig</name>

<packaging>war</packaging>

<version>1.0.0-BUILD-SNAPSHOT</version>

<properties>

<!-- 자바 버전 변경함 -->

<java-version>14</java-version>

<!-- 스프링프레임워크 버전 변경함 -->

<org.springframework-version>5.2.9.RELEASE</org.springframework-version>

<!-- AspectJ 변경함 -->

<org.aspectj-version>1.9.6</org.aspectj-version>

<org.slf4j-version>1.6.6</org.slf4j-version>

</properties>

<dependencies>

<!-- Spring -->

<dependency>

<groupId>org.springframework</groupId>

<artifactId>spring-context</artifactId>

<version>${org.springframework-version}</version>

<exclusions>

<!-- Exclude Commons Logging in favor of SLF4j -->

<exclusion>

<groupId>commons-logging</groupId>

<artifactId>commons-logging</artifactId>

</exclusion>

</exclusions>

</dependency>

<dependency>

<groupId>org.springframework</groupId>

<artifactId>spring-webmvc</artifactId>

<version>${org.springframework-version}</version>

</dependency>

<!-- AspectJ 버전 변경 -->

<dependency>

<groupId>org.aspectj</groupId>

<artifactId>aspectjrt</artifactId>

<version>${org.aspectj-version}</version>

</dependency>

<!-- AspectJWeaver 추가 -->

<dependency>

<groupId>org.aspectj</groupId>

<artifactId>aspectjweaver</artifactId>

<version>${org.aspectj-version}</version>

</dependency>

<!-- Logging -->

<dependency>

<groupId>org.slf4j</groupId>

<artifactId>slf4j-api</artifactId>

<version>${org.slf4j-version}</version>

</dependency>

<dependency>

<groupId>org.slf4j</groupId>

<artifactId>jcl-over-slf4j</artifactId>

<version>${org.slf4j-version}</version>

<scope>runtime</scope>

</dependency>

<dependency>

<groupId>org.slf4j</groupId>

<artifactId>slf4j-log4j12</artifactId>

<version>${org.slf4j-version}</version>

<scope>runtime</scope>

</dependency>

<dependency>

<groupId>log4j</groupId>

<artifactId>log4j</artifactId>

<version>1.2.15</version>

<exclusions>

<exclusion>

<groupId>javax.mail</groupId>

<artifactId>mail</artifactId>

</exclusion>

<exclusion>

<groupId>javax.jms</groupId>

<artifactId>jms</artifactId>

</exclusion>

<exclusion>

<groupId>com.sun.jdmk</groupId>

<artifactId>jmxtools</artifactId>

</exclusion>

<exclusion>

<groupId>com.sun.jmx</groupId>

<artifactId>jmxri</artifactId>

</exclusion>

</exclusions>

<scope>runtime</scope>

</dependency>

<!-- @Inject -->

<dependency>

<groupId>javax.inject</groupId>

<artifactId>javax.inject</artifactId>

<version>1</version>

</dependency>

      <!-- Servlet -->

            <!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api --> 

            <dependency> 

                  <groupId>javax.servlet</groupId>

                  <artifactId>javax.servlet-api</artifactId>

                  <version>4.0.1</version>

                  <scope>provided</scope> 

            </dependency>

<dependency>

<groupId>javax.servlet.jsp</groupId>

<artifactId>jsp-api</artifactId>

<version>2.1</version>

<scope>provided</scope>

</dependency>

<dependency>

<groupId>javax.servlet</groupId>

<artifactId>jstl</artifactId>

<version>1.2</version>

</dependency>

<!-- Test -->

<dependency>

<groupId>junit</groupId>

<artifactId>junit</artifactId>

<version>4.7</version>

<scope>test</scope>

</dependency>        

</dependencies>

    <build>

        <plugins>

            <plugin>

                <artifactId>maven-eclipse-plugin</artifactId>

                <version>2.9</version>

                <configuration>

                    <additionalProjectnatures>

                        <projectnature>org.springframework.ide.eclipse.core.springnature</projectnature>

                    </additionalProjectnatures>

                    <additionalBuildcommands>

                        <buildcommand>org.springframework.ide.eclipse.core.springbuilder</buildcommand>

                    </additionalBuildcommands>

                    <downloadSources>true</downloadSources>

                    <downloadJavadocs>true</downloadJavadocs>

                </configuration>

            </plugin>

            <plugin>

                <groupId>org.apache.maven.plugins</groupId>

                <artifactId>maven-compiler-plugin</artifactId>

                <version>2.5.1</version>

                <configuration>

                    <source>1.6</source>

                    <target>1.6</target>

                    <compilerArgument>-Xlint:all</compilerArgument>

                    <showWarnings>true</showWarnings>

                    <showDeprecation>true</showDeprecation>

                </configuration>

            </plugin>

            <plugin>

                <groupId>org.codehaus.mojo</groupId>

                <artifactId>exec-maven-plugin</artifactId>

                <version>1.2.1</version>

                <configuration>

                    <mainClass>org.test.int1.Main</mainClass>

                </configuration>

            </plugin>

        </plugins>

    </build>

</project>

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"

    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"

    version="4.0">

<!-- The definition of the Root Spring Container shared by all Servlets and Filters -->

<context-param>

<param-name>contextConfigLocation</param-name>

<param-value>/WEB-INF/spring/root-context.xml</param-value>

</context-param>

<!-- Creates the Spring Container shared by all Servlets and Filters -->

<listener>

<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>

</listener>

<!-- Processes application requests -->

<servlet>

<servlet-name>appServlet</servlet-name>

<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

<init-param>

<param-name>contextConfigLocation</param-name>

<param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>

</init-param>

<load-on-startup>1</load-on-startup>

</servlet>

<servlet-mapping>

<servlet-name>appServlet</servlet-name>

<url-pattern>/</url-pattern>

</servlet-mapping>

</web-app>

package com.local.example.service;

public class Calculator {

private long x;

private long y;

private long z;

public Calculator(long x, long y, long z) {

this.x = x;

this.y = y;

this.z = z;

}

// 작업 원본(A 프로그래머 작성함)

public long sum() {

long result = x + y + z;

return result;

}

}

참고로 지금 코드로는 AspectJ가 동작되지 않는 코드이다.
이유는 초기 매개변수가 없는 생성자가 없어서 그렇다.

(다음 페이지에서 소개하겠음.)

package com.local.example;

import java.text.DateFormat;

import java.util.Date;

import java.util.Locale;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import org.springframework.context.annotation.EnableAspectJAutoProxy;

import org.springframework.stereotype.Controller;

import org.springframework.ui.Model;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import com.local.example.aop.Calculator;

import com.local.example.aop.RootConfig;

/**

 * Handles requests for the application home page.

 */

public class HomeController {

private static final Logger logger = LoggerFactory.getLogger(HomeController.class);

/**

* Simply selects the home view to render by returning its name.

*/

@RequestMapping(value = "/", method = RequestMethod.GET)

public String home(Locale locale, Model model) {

logger.info("Welcome home! The client locale is {}.", locale);

Date date = new Date();

DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG, DateFormat.LONG, locale);

String formattedDate = dateFormat.format(date);

Calculator cal = new Calculator(1, 2, 3);

System.out.printf("result of sum: %d", cal.sum());

model.addAttribute("serverTime", formattedDate );

return "home";

}

}

1. [Spring-Framework] 30. AOP(Aspect-Oriented-Programming) 관점지향 프로그래밍 (Java셋팅) (2), 2020-10-04

https://yyman.tistory.com/1448

1. [JSP] 18. JSP/Servlet MVC2 - 페이징네이션과 검색 그리고 오라클 프로젝트 (1)

https://yyman.tistory.com/1428

실제경로: /target/generated-sources/annotations/com/smile/web/model

패키지명: com.smile.web.logic

파일명: Paging.java

package com.smile.web.logic;

public class Paging {

    private long pageSize; // 게시 글 수

    private long firstPageNo; // 첫 번째 페이지 번호

    private long prevPageNo; // 이전 페이지 번호

    private long startPageNo; // 시작 페이지 (페이징 네비 기준)

    private long pageNo; // 페이지 번호

    private long endPageNo; // 끝 페이지 (페이징 네비 기준)

    private long nextPageNo; // 다음 페이지 번호

    private long finalPageNo; // 마지막 페이지 번호

    private long totalCount; // 게시 글 전체 수

    private long dbStartNum; // db 조회 (시작번호)

    private long dbEndNum; // db 조회 (종료번호)

    /**

     * @return the pageSize

     */

    public long getPageSize() {

        return pageSize;

    }

    /**

     * @param pageSize the pageSize to set

     */

    public void setPageSize(long pageSize) {

        this.pageSize = pageSize;

    }

    /**

     * @return the firstPageNo

     */

    public long getFirstPageNo() {

        return firstPageNo;

    }

    /**

     * @param firstPageNo the firstPageNo to set

     */

    public void setFirstPageNo(long firstPageNo) {

        this.firstPageNo = firstPageNo;

    }

    /**

     * @return the prevPageNo

     */

    public long getPrevPageNo() {

        return prevPageNo;

    }

    /**

     * @param prevPageNo the prevPageNo to set

     */

    public void setPrevPageNo(long prevPageNo) {

        this.prevPageNo = prevPageNo;

    }

    /**

     * @return the startPageNo

     */

    public long getStartPageNo() {

        return startPageNo;

    }

    /**

     * @param startPageNo the startPageNo to set

     */

    public void setStartPageNo(long startPageNo) {

        this.startPageNo = startPageNo;

    }

    /**

     * @return the pageNo

     */

    public long getPageNo() {

        return pageNo;

    }

    /**

     * @param pageNo the pageNo to set

     */

    public void setPageNo(long pageNo) {

        this.pageNo = pageNo;

    }

    /**

     * @return the endPageNo

     */

    public long getEndPageNo() {

        return endPageNo;

    }

    /**

     * @param endPageNo the endPageNo to set

     */

    public void setEndPageNo(long endPageNo) {

        this.endPageNo = endPageNo;

    }

    /**

     * @return the nextPageNo

     */

    public long getNextPageNo() {

        return nextPageNo;

    }

    /**

     * @param nextPageNo the nextPageNo to set

     */

    public void setNextPageNo(long nextPageNo) {

        this.nextPageNo = nextPageNo;

    }

    /**

     * @return the finalPageNo

     */

    public long getFinalPageNo() {

        return finalPageNo;

    }

    /**

     * @param finalPageNo the finalPageNo to set

     */

    public void setFinalPageNo(long finalPageNo) {

        this.finalPageNo = finalPageNo;

    }

    /**

     * @return the totalCount

     */

    public long getTotalCount() {

        return totalCount;

    }

    /**

     * @param totalCount the totalCount to set

     */

    public void setTotalCount(long totalCount) {

        this.totalCount = totalCount;

        this.makePaging();

        this.makeDbPaging();

    }

    /**

     * 페이징 생성 (setTotalCount에서 호출함)

     */

    private void makePaging() {

        if (this.totalCount == 0) 

        return; 

        // 게시 글 전체 수가 없는 경우

        if (this.pageNo == 0) 

        this.setPageNo(1); // 기본 값 설정

        if (this.pageSize == 0) 

        this.setPageSize(10); // 기본 값 설정

        long finalPage = (totalCount + (pageSize - 1)) / pageSize; // 마지막 페이지

        if (this.pageNo > finalPage) 

        this.setPageNo(finalPage); // 기본 값 설정

        if (this.pageNo < 0 || this.pageNo > finalPage) 

        this.pageNo = 1; // 현재 페이지 유효성 체크

        boolean isNowFirst = pageNo == 1 ? true : false; // 시작 페이지 (전체)

        boolean isNowFinal = pageNo == finalPage ? true : false; // 마지막 페이지 (전체)

        long startPage = ((pageNo - 1) / 10) * 10 + 1; // 시작 페이지 (페이징 네비 기준)

        long endPage = startPage + 10 - 1; // 끝 페이지 (페이징 네비 기준)

        if (endPage > finalPage) { // [마지막 페이지 (페이징 네비 기준) > 마지막 페이지] 보다 큰 경우

            endPage = finalPage;

        }

        this.setFirstPageNo(1); // 첫 번째 페이지 번호

        if (isNowFirst) {

            this.setPrevPageNo(1);    // 이전 페이지 번호

        } else {

            this.setPrevPageNo(((pageNo - 1) < 1 ? 1 : (pageNo - 1))); // 이전 페이지 번호

        }

        this.setStartPageNo(startPage); // 시작 페이지 (페이징 네비 기준)

        this.setEndPageNo(endPage); // 끝 페이지 (페이징 네비 기준)

        if (isNowFinal) {

            this.setNextPageNo(finalPage); // 다음 페이지 번호

        } else {

            this.setNextPageNo(((pageNo + 1) > finalPage ? finalPage : (pageNo + 1))); // 다음 페이지 번호

        }

        this.setFinalPageNo(finalPage); // 마지막 페이지 번호

    }

    private void makeDbPaging() {

    long current = this.getPageNo();

    long weight = this.getPageSize();

    long endNum = 0;

    this.setDbEndNum( current * weight );

    endNum = this.getDbEndNum();

    this.setDbStartNum( (endNum - weight) + 1 );

    }

    /**

     * @return the dbStartNum

     */

public long getDbStartNum() {

return dbStartNum;

}

    /**

     * @param dbStartNum the dbStartNum to set

     */

public void setDbStartNum(long dbStartNum) {

this.dbStartNum = dbStartNum;

}

    /**

     * @return dbEndNum

     */

public long getDbEndNum() {

return dbEndNum;

}

    /**

     * @param dbEndNum the dbEndNum to set

     */

public void setDbEndNum(long dbEndNum) {

this.dbEndNum = dbEndNum;

}

}

실제경로: /target/generated-sources/annotations/com/smile/web/model

패키지명: com.smile.web.model

파일명: Board.java

package com.smile.web.model;

import java.sql.Timestamp;

public class Board {

private long id;

private String name;

private String subject;

private String memo;

private long count;

private Timestamp regidate;

public long getId() {

return id;

}

public void setId(long id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getSubject() {

return subject;

}

public void setSubject(String subject) {

this.subject = subject;

}

public String getMemo() {

return memo;

}

public void setMemo(String memo) {

this.memo = memo;

}

public long getCount() {

return count;

}

public void setCount(long count) {

this.count = count;

}

public Timestamp getRegidate() {

return regidate;

}

public void setRegidate(Timestamp regidate) {

this.regidate = regidate;

}

}

실제경로: /target/generated-sources/annotations/com/smile/web/service

패키지명: com.smile.web.service

파일명: BoardService.java

package com.smile.web.service;

import java.util.List;

import com.smile.web.model.Board;

public class BoardService {

private static BoardService service = null;

private static BoardServiceImpl dao = null;

private BoardService() {}

public static BoardService getInstance() {

        if(service == null){

        service = new BoardService();

    dao = BoardServiceImpl.getInstatnce();

        }

        return service;

}

public List<Board> getBoardList(long startNum, long endNum){

return dao.getBoardList(startNum, endNum);

}

public long getTotalCount() {

return dao.getTotalCount();

}

public List<Board> getBoardKeywordList(String keyword, long startNum, long endNum){

return dao.getBoardKeywordList(keyword, startNum, endNum);

}

public long getTotalKeywordCount(String keyword) {

return dao.getTotalKeywordCount(keyword);

}

}

실제경로: /target/generated-sources/annotations/com/smile/web/service

패키지명: com.smile.web.service

파일명: BoardServiceImpl.java

package com.smile.web.service;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.List;

import com.smile.web.db.DBFactory;

import com.smile.web.model.Board;

public class BoardServiceImpl {

private static BoardServiceImpl boardDAO;

private static DBFactory dbPool;

private BoardServiceImpl() {}

public static BoardServiceImpl getInstatnce() {

if ( boardDAO == null ) {

boardDAO = new BoardServiceImpl();

dbPool = new DBFactory();

}

return boardDAO;

}

public List<Board> getBoardList(long startNum, long endNum){

Connection conn = null;

    PreparedStatement pstmt = null;

    ResultSet rs = null;

    Board node = null;

    List<Board> boardList = new ArrayList<Board>();

    String sql = "select * from (select /*+INDEX_DESC(tbl_board pk_board) */ rownum rn, A.*" + 

    " from board A order by id desc) " + 

    "where rn >= ? and rn <= ?";

    //System.out.println(sql);

    //System.out.println(startNum + "/" + endNum);

    try {

    conn = dbPool.getConnection();

    pstmt = conn.prepareStatement(sql);

    pstmt.setLong(1, startNum);

    pstmt.setLong(2, endNum);

    rs = pstmt.executeQuery();

    while ( rs.next() ) {

    // 데이터가 존재할 때, 노드 생성

    node = new Board();

    node.setId(rs.getLong(2));

    node.setSubject(rs.getNString(3));

    node.setMemo(rs.getNString(4));

    node.setName(rs.getNString(5));

    boardList.add(node);

    System.out.println("rs:" + rs.getLong(1));

    }

    }catch(Exception ex) {

    System.out.println("오류 발생: " + ex);

    }

    finally {

    dbPool.close(conn, pstmt, rs);

    }

return boardList;

}

public List<Board> getBoardKeywordList(String keyword, long startNum, long endNum){

Connection conn = null;

    PreparedStatement pstmt = null;

    ResultSet rs = null;

    Board node = null;

    String allKeyword = "%" + keyword + "%";

    List<Board> boardList = new ArrayList<Board>();

    String sql = "select * " + 

    "from (select /*+INDEX_DESC(tbl_board pk_board) */ rownum rn, A.* " + 

    "from board A where subject like ? order by id desc) " + 

    "where rn >= ? and rn <= ?";

    //System.out.println(sql);

    try {

    conn = dbPool.getConnection();

    pstmt = conn.prepareStatement(sql);

    pstmt.setNString(1, allKeyword);

    pstmt.setLong(2, startNum);

    pstmt.setLong(3, endNum);

    rs = pstmt.executeQuery();

    while ( rs.next() ) {

    // 데이터가 존재할 때, 노드 생성

    node = new Board();

    node.setId(rs.getLong(2));

    node.setSubject(rs.getNString(3));

    node.setMemo(rs.getNString(4));

    node.setName(rs.getNString(5));

    boardList.add(node);

    //System.out.println("rs:" + rs.getLong(1));

    }

    }catch(Exception ex) {

    System.out.println("오류 발생: " + ex);

    }

    finally {

    dbPool.close(conn, pstmt, rs);

    }

return boardList;

}

public long getTotalCount() {

Connection conn = null;

    PreparedStatement pstmt = null;

    ResultSet rs = null;

    Board node = null;

    long cnt = 0;

    String sql = "select count(*) from board";

    System.out.println("sql:" + sql);

    try {

    conn = dbPool.getConnection();

    //System.out.println( conn.getSchema() );

    pstmt = conn.prepareStatement(sql);

    rs = pstmt.executeQuery();

    //System.out.println( rs.getFetchSize() );

    if ( rs.next() ) {

    cnt = rs.getLong(1);

        System.out.println("전체갯수:" + cnt + "/" + rs.getLong(1));

    }

    }catch(Exception ex) {

    System.out.println("오류 발생: " + ex);

    }

    finally {

    dbPool.close(conn, pstmt, rs);

    }

return cnt;

}

public long getTotalKeywordCount(String keyword) {

Connection conn = null;

    PreparedStatement pstmt = null;

    ResultSet rs = null;

    Board node = null;

    String allKeyword = "%" + keyword + "%";

    long cnt = 0;

    String sql = "select count(*) from board where subject like ?";

    //System.out.println("sql:" + sql + "/키:" + keyword);

    try {

    conn = dbPool.getConnection();

    /// System.out.println( conn.getSchema() );

    pstmt = conn.prepareStatement(sql);

    pstmt.setNString(1, allKeyword);

    rs = pstmt.executeQuery();

    /// System.out.println( rs.getFetchSize() );

    if ( rs.next() ) {

    cnt = rs.getLong(1);

        System.out.println("특정 갯수:" + cnt + "/" + rs.getLong(1));

    }

    }catch(Exception ex) {

    System.out.println("오류 발생: " + ex);

    }

    finally {

    dbPool.close(conn, pstmt, rs);

    }

return cnt;

}

}

[개선 후 SQL 파일 내용]

-- Oracle 11 - 자동번호 생성 테이블 정의
-- Table 생성 (BOARD)
-- NEW.ID (Table의 id를 가리킴)
CREATE TABLE board
(
    id NUMBER PRIMARY KEY,
    name VARCHAR2(30),
    subject VARCHAR2(30),
    memo NCLOB,
    count NUMBER,
    regidate DATE
);

-- Sequence 정의
CREATE SEQUENCE board_sequence
START WITH 1
INCREMENT BY 1;

-- Trigger 생성
-- BEFORE INSERT on '테이블명'
CREATE OR REPLACE TRIGGER board_trigger
BEFORE INSERT
    ON board
REFERENCING NEW AS NEW
FOR EACH ROW
BEGIN
SELECT board_sequence.nextval INTO :NEW.ID FROM dual;
END;

/* 데이터 추가 */
INSERT INTO board (name, subject, memo, count, regidate) VALUES ('홍길동', '안녕하세요.', '메모메모', '0', '2020-09-29 11:11:00');

/* 데이터 등록 후 커밋할 것(대량 정보 처리 후) */
COMMIT;

-- 싱글 쿼리 (페이징)
SELECT * FROM (
SELECT /*+ INDEX_DESC(Z OP_SAMPLE_PK) */ ROWNUM AS RNUM, Z.* FROM (
SELECT * from board order by id desc
) Z WHERE ROWNUM <= 10
) WHERE RNUM >= 1

-- 특정 싱글 쿼리 SQL
SELECT * FROM (
SELECT /*+ INDEX_DESC(Z OP_SAMPLE_PK) */ ROWNUM AS RNUM, Z.* FROM (
SELECT * from board where subject like '%야해해%' order by id desc
) Z WHERE ROWNUM <= 10
) WHERE RNUM >= 1

페이징 로직 설계가 되었다면, 다음 계획해야 할 작업이 실질적으로는 이 작업이다.

의외로 작업을 하다보면, 골치가 아픈 문제들이 많이 생긴다.

[Oracle Databases 코너에 쿼리 관련 작업에 대해서 추가로 보충하여 소개하도록 하겠다.]

- 단일 테이블 게시물 쿼리 방법, 뷰 테이블 쿼리 방법, 테이블 조인(2개 이상) 사용 방법

-> 태스트 결과로는 "Java 페이징 로직"은 크게 문제가 없다. 
    다만, 나머지 부분은 쿼리라고 본다.

생성할 폴더: 

/src/main/webapp/board

/src/main/webapp/board/css

생성할 파일

/src/main/web/app/board/css/style.css

@charset "utf-8";

/* 1. 제목 */

h3{

font-size:20px;

font-family:'Nanum Gothic';

text-align:center;

}

/* 2. 게시판 */

/* 게시판 목록 출력 */

.board_list{

border-top:1px solid #e2e2e2;

border-bottom:1px solid #e2e2e2;

font-size:12px;

font-family:'Nanum Gothic';

width:900px;

margin:auto;

text-align:center;

}

/* 제목 */

.board_list th{

border-right:1px solid #666;

border-bottom:1px solid #666;

font-size:15px;

font-family:'Nanum Gothic';

height:20px;

text-align:center;

background-color:#eeeeee;

}

/* 내용 */

.board_list td{

border-right:1px solid #e2e2e2;

font-size:15px;

font-family:'Nanum Gothic';

height:20px;

text-align:center;

}

/* 3. 페이징 네이션 */

.paginate{

font-size:15px;

font-family:'Nanum Gothic';

font-color:#666;

text-align: center;

}

.paginate .first{

font-size:15px;

font-family:'Nanum Gothic';

font-color:#666;

text-align: center;

margin-right:10px;

}

.paginate .prev{

font-size:15px;

font-family:'Nanum Gothic';

font-color:#666;

text-align: center;

margin-right:10px;

}

.paginate .next{

font-size:15px;

font-family:'Nanum Gothic';

font-color:#666;

text-align: center;

margin-right:10px;

}

.paginate .last{

font-size:15px;

font-family:'Nanum Gothic';

font-color:#666;

text-align: center;

margin-right:10px;

}

.paginate .choice{

font-size:20px;

font-family:'Nanum Gothic';

font-color:#666;

text-align: center;

margin-right:10px;

}

/* 4. 링크 */

a{

text-decoration:none;

color:#666;

}

/* 5. 검색 영역 */

.searchArea{

font-size:15px;

font-family:'Nanum Gothic';

font-color:#666;

text-align: center;

}

생성할 폴더: 

/src/main/webapp/WEB-INF/views/

/src/main/webapp/WEB-INF/views/board

생성할 파일

/src/main/webapp/WEB-INF/views/board/list.jsp

/src/main/webapp/WEB-INF/views/board/search.jsp

/src/main/webapp/WEB-INF/views/board/paging.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<%@ page import = "java.util.*" %>

<%@ page import = "com.smile.web.model.*" %>

<%@ page session="false" %>

<!DOCTYPE html>

<html>

<head>

<meta charset="UTF-8">

<title>게시물 목록</title>

<style>

@import url('https://fonts.googleapis.com/css?family=Nanum+Gothic:400,700,800');

</style>

<link href="css/style.css" rel="stylesheet" type="text/css" />

</head>

<body>

<%

List<Board> boardList = (List<Board>)request.getAttribute("list");

%>

<h3>게시물 목록</h3>

<!-- 목록 출력 -->

<table class="board_list">

<tr>

<th style="width:15%;">

번호(Num)

</th>

<th>

제목(Subject)

</th>

<th style="width:13%;">

글쓴이(Author)

</th>

<th style="width:13%; border-right:none;">

조회수(Count)

</th>

</tr>

<%

for(Board board:boardList){

%>

<tr>

<td style="width:15%;">

<%= board.getId() %>

</td>

<td>

<%= board.getSubject() %>

</td>

<td style="width:13%;">

<%= board.getName() %>

</td>

<td style="width:13%; border-right:none;">

<%= board.getCount() %>

</td>

</tr>

<%

}

%>

</table>

<!-- 페이징 -->

<jsp:include page="/WEB-INF/views/board/paging.jsp">

<jsp:param name="customURL" value="${pagingUrl}" />

    <jsp:param name="firstPageNo" value="${paging.firstPageNo}" />

    <jsp:param name="prevPageNo" value="${paging.prevPageNo}" />

    <jsp:param name="startPageNo" value="${paging.startPageNo}" />

    <jsp:param name="pageNo" value="${paging.pageNo}" />

    <jsp:param name="endPageNo" value="${paging.endPageNo}" />

    <jsp:param name="nextPageNo" value="${paging.nextPageNo}" />

    <jsp:param name="finalPageNo" value="${paging.finalPageNo}" />

</jsp:include>

<!-- 검색 -->

<jsp:include page="/WEB-INF/views/board/search.jsp" />

</body>

</html>

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

<div class="paginate">

    <a href="${param.customURL}page=${param.firstPageNo}" class="first">처음 페이지</a>

    <a href="${param.customURL}page=${param.prevPageNo}" class="prev">이전 페이지</a>

    <span>

        <c:forEach var="i" begin="${param.startPageNo}" end="${param.endPageNo}" step="1">

            <c:choose>

                <c:when test="${i eq param.pageNo}"><a href="${param.customURL}page=${i}" class="choice">${i}</a></c:when>

                <c:otherwise><a href="${param.customURL}page=${i}">${i}</a></c:otherwise>

            </c:choose>

        </c:forEach>

    </span>

    <a href="${param.customURL}page=${param.nextPageNo}" class="next">다음 페이지</a>

    <a href="${param.customURL}page=${param.finalPageNo}" class="last">마지막 페이지</a>

</div>

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

<div class="searchArea">

<form id="searchForm" action="list.do" method='get'>

<select name="type">

<option value="T">제목</option>

<option value="C">내용</option>

<option value="W">작성자</option>

</select>

<input type="text" name="keyword">

<button class="">검색</button>

</form>

</div>

IDE: Spring-Tool Suite 4-4.7.2 RELEASES

Databases: Oracle Databases 19g

 - Maven 3.6.3/1.16.0.20200610-1735

 - javax.servlet-api (4.0.1) - servlet(서블렛)

 - jstl (1.2) - jstl 태그 적용

 - taglibs (1.1.2) - c태그 적용

 - HikariCP (3.4.2) - 커넥션 풀

 - com.oracle.database.jdbc - ojdbc8 (19.7.0.0)

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

  <modelVersion>4.0.0</modelVersion>

  <groupId>com.boardMaven</groupId>

  <artifactId>web</artifactId>

  <version>0.0.1-SNAPSHOT</version>

  <packaging>war</packaging>

  <name>board Maven Webapp</name>

  <!-- FIXME change it to the project's website -->

  <url>http://www.example.com</url>

  <properties>

    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

    <maven.compiler.source>1.7</maven.compiler.source>

    <maven.compiler.target>1.7</maven.compiler.target>

  </properties>

  <dependencies>

    <dependency>

      <groupId>junit</groupId>

      <artifactId>junit</artifactId>

      <version>4.11</version>

      <scope>test</scope>

    </dependency>

<!-- Servlet -->

<!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->

<dependency>

    <groupId>javax.servlet</groupId>

    <artifactId>javax.servlet-api</artifactId>

    <version>4.0.1</version>

    <scope>provided</scope>

</dependency>

<!-- JSTL -->

<dependency>

<groupId>javax.servlet</groupId>

<artifactId>jstl</artifactId>

<version>1.2</version>

</dependency>

<!-- taglibs -->

<dependency>

<groupId>taglibs</groupId>

<artifactId>standard</artifactId>

<version>1.1.2</version>

<scope>compile</scope>

</dependency>

<!-- https://mvnrepository.com/artifact/com.zaxxer/HikariCP -->

<dependency>

    <groupId>com.zaxxer</groupId>

    <artifactId>HikariCP</artifactId>

    <version>3.4.2</version>

</dependency>

<dependency>

<groupId>com.oracle.database.jdbc</groupId>

<artifactId>ojdbc8</artifactId>

<version>19.7.0.0</version>

</dependency>

  </dependencies>

  <build>

    <finalName>board</finalName>

    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->

      <plugins>

        <plugin>

          <artifactId>maven-clean-plugin</artifactId>

          <version>3.1.0</version>

        </plugin>

        <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->

        <plugin>

          <artifactId>maven-resources-plugin</artifactId>

          <version>3.0.2</version>

        </plugin>

        <plugin>

          <artifactId>maven-compiler-plugin</artifactId>

          <version>3.8.0</version>

        </plugin>

        <plugin>

          <artifactId>maven-surefire-plugin</artifactId>

          <version>2.22.1</version>

        </plugin>

        <plugin>

          <artifactId>maven-war-plugin</artifactId>

          <version>3.2.2</version>

        </plugin>

        <plugin>

          <artifactId>maven-install-plugin</artifactId>

          <version>2.5.2</version>

        </plugin>

        <plugin>

          <artifactId>maven-deploy-plugin</artifactId>

          <version>2.8.2</version>

        </plugin>

      </plugins>

    </pluginManagement>

  </build>

</project>

폴더명: Resource

파일명: db.properties

jdbcUrl=jdbc:oracle:thin:@localhost:1521:orcl

dataSourceClassName=oracle.jdbc.driver.OracleDriver

dataSource.user=userName

dataSource.password=password

cachePrepStmts=true

prepStmtCacheSize=250

prepStmtCacheSqlLimit=2048

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 

xmlns="http://java.sun.com/xml/ns/javaee" 

xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" 

id="WebApp_ID" version="3.0">

  <display-name>Archetype Created Web Application</display-name>

  <servlet>

  <servlet-name>FrontController</servlet-name>

  <servlet-class>com.smile.web.controller.FrontController</servlet-class>

  <init-param>

<param-name>charset</param-name>

<param-value>UTF-8</param-value>

</init-param>

  </servlet>

  <servlet-mapping>

  <servlet-name>FrontController</servlet-name>

  <url-pattern>*.do</url-pattern>

  </servlet-mapping>

</web-app>

폴더1: /src/main/webapp/WEB-INF/settings

폴더2: /src/main/webapp/WEB-INF/views

파일: /src/main/webapp/WEB-INF/settings/root-servlet.xml

실제경로: /target/generated-sources/annotations/com/smile/web/controller

패키지명: com.smile.web.controller

파일명: FrontController.java

package com.smile.web.controller;

import java.io.IOException;

import java.sql.SQLException;

import javax.servlet.ServletConfig;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.smile.web.db.DBFactory;

public class FrontController extends HttpServlet {

private static final long serialVersionUID = 1L;

private String charset = null;

/**

* @see HttpServlet#doGet(HttpServletRequest req, HttpServletResponse res)

*/

protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

doAction(req, res);

}

/**

* @see HttpServlet#doPost(HttpServletRequest req, HttpServletResponse res)

*/

protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

doAction(req, res);

}

// FrontController 패턴 & Command 패턴

protected void doAction(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

ServletConfig sc = this.getServletConfig();

charset = sc.getInitParameter("charset");

req.setAttribute("charset", charset);

req.setCharacterEncoding(charset);

res.setContentType("text/html; charset=" + charset);

String uri = req.getRequestURI();

String conPath = req.getContextPath();

String command = uri.substring(conPath.length());

Controller subController = null;

if(command.equals("/board/list.do")){

System.out.println("-----------------------------");

System.out.println("게시판 목록");

System.out.println("-----------------------------");

req.setAttribute("controllerName", "list");

subController = new com.smile.web.controller.board.ListController();

subController.execute(req, res);

}

}

}

실제경로: /target/generated-sources/annotations/com/smile/web/controller

패키지명: com.smile.web.controller

파일명: Controller.java

package com.smile.web.controller;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

public interface Controller {

public void execute(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException;

}

실제경로: /target/generated-sources/annotations/com/smile/web/controller/board

패키지명: com.smile.web.controller.board

파일명: ListController.java

package com.smile.web.controller.board;

import java.io.IOException;

import java.net.URLEncoder;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.smile.web.controller.Controller;

import com.smile.web.logic.Paging;

import com.smile.web.model.Board;

import com.smile.web.service.BoardService;

import com.smile.web.util.HttpUtil;

public class ListController implements Controller {

@Override

public void execute(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {

String controllerName = (String) req.getAttribute("controllerName");

BoardService service = BoardService.getInstance();

List<Board> boardList = null;

// long totalCount = boardList.size();

long currentPage = 1; // 기본값

long pageSize = 10;

long totalCount = service.getTotalCount();

long startNum, endNum;

String keyword = null;

String pagingUrl = controllerName + ".do?";

// 페이지 번호 존재할 때

if (req.getParameter("page") != null){

currentPage = Integer.valueOf( req.getParameter("page") );

}

// 키워드가 존재할 때

if (req.getParameter("keyword") != null) {

keyword = req.getParameter("keyword");

totalCount = service.getTotalKeywordCount(keyword);

// 키워드 값이 하나라도 존재할 때

if ( keyword.length() > 0) {

pagingUrl = pagingUrl + "keyword=" + URLEncoder.encode(keyword, "UTF-8") + "&";

}

}

        Paging paging = new Paging();

        /*

        paging.setPageNo(1);

        paging.setPageSize(10);

        paging.setTotalCount(totalCount);

        */

        paging.setPageNo(currentPage);

        paging.setPageSize(pageSize);

        paging.setTotalCount(totalCount);

        System.out.println("현재페이지번호:" + currentPage);

        System.out.println("페이지크기:" + pageSize);

        System.out.println("키워드:" + keyword);

        System.out.println("페이징URL:" + pagingUrl);

        startNum = paging.getDbStartNum();

        endNum = paging.getDbEndNum();

// 키워드가 존재할 때

if (keyword != null) {

// 키워드 값이 하나라도 존재할 때

if ( keyword.length() > 0) {

boardList = service.getBoardKeywordList(keyword, startNum, endNum);

}

else {

boardList = service.getBoardList(startNum, endNum);

}

}

else {

        boardList = service.getBoardList(startNum, endNum);

}

        req.setAttribute("paging", paging);

        req.setAttribute("list", boardList);

        req.setAttribute("pagingUrl", pagingUrl);

HttpUtil.forward(req, res, "/WEB-INF/views/board/" + controllerName + ".jsp");

}

}

실제경로: /target/generated-sources/annotations/com/smile/web/util

패키지명: com.smile.web.controller.util

파일명: HttpUtil.java

package com.smile.web.util;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.io.PrintWriter;

import javax.servlet.RequestDispatcher;

import javax.servlet.ServletConfig;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

public class HttpUtil extends HttpServlet {

private static final long serialVersionUID = 1L;

private static String charset = null;

public static void forward(HttpServletRequest req, HttpServletResponse res,

String path) throws ServletException, IOException {

try {

RequestDispatcher dispatcher = req.getRequestDispatcher(path);

dispatcher.forward(req, res);

}catch(Exception e) {

e.printStackTrace();

}

}

public static void fileUpload(HttpServletRequest req, HttpServletResponse res,

String path) throws ServletException, IOException {

charset = (String) req.getAttribute("charset");

System.out.println(charset);

PrintWriter out = res.getWriter();

// 파일 업로드된 경로

String root = req.getSession().getServletContext().getRealPath("/");

String savePath = root + "upload" + File.separator + "upload";

// 서버에 실제 저장된 파일명

String filename = "1600955663095" ;

System.out.println("파일 실제 폴더경로:" + savePath);

// 실제 내보낼 파일명

String orgfilename = "license한글.txt" ;

req.setCharacterEncoding(charset);

res.setCharacterEncoding(charset);

InputStream in = null;

OutputStream os = null;

File file = null;

boolean skip = false;

String client = "";

try{

    // 파일을 읽어 스트림에 담기

    try{

        file = new File(savePath, filename);

        in = new FileInputStream(file);

    }catch(FileNotFoundException fe){

        skip = true;

    }

    client = req.getHeader("User-Agent");

    // 파일 다운로드 헤더 지정

    res.reset() ;

    res.setContentType("application/octet-stream");

    res.setHeader("Content-Description", "JSP Generated Data");

    if(!skip){

        // IE

        if(client.indexOf("MSIE") != -1){

            res.setHeader ("Content-Disposition", "attachment; filename="+new String(orgfilename.getBytes("KSC5601"),"ISO8859_1"));

        }else{

            // 한글 파일명 처리

            orgfilename = new String(orgfilename.getBytes("KSC5601"),"iso-8859-1");

            res.setHeader("Content-Disposition", "attachment; filename=\"" + orgfilename + "\"");

            res.setHeader("Content-Type", "application/octet-stream; charset=utf-8");

        }  

        res.setHeader ("Content-Length", ""+file.length() );

        os = res.getOutputStream();

        byte b[] = new byte[(int)file.length()];

        int leng = 0;

        while( (leng = in.read(b)) > 0 ){

            os.write(b,0,leng);

        }

    }else{

    // 한글 깨짐 - 해결

    res.setContentType("text/html;charset=" + charset);

        out.println("<html><head>");

        out.println("<script language='javascript'>alert('파일을 찾을 수 없습니다.');history.back();</script>");

        out.println("</head><body></body></html>");

    }

    in.close();

    os.close();

}catch(Exception e){

e.printStackTrace();

}

}

}

실제경로: /target/generated-sources/annotations/com/smile/web/db

패키지명: com.smile.web.controller.db

파일명: DBFactory.java

package com.smile.web.db;

import java.io.IOException;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.Properties;

import java.io.IOException;

import java.io.InputStream;

import java.io.Reader;

import java.util.Properties;

import java.sql.Connection;

import java.sql.SQLException;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import com.zaxxer.hikari.HikariConfig;

import com.zaxxer.hikari.HikariDataSource;

import oracle.jdbc.pool.OracleDataSource;

public class DBFactory {

private static final Logger logger = LoggerFactory.getLogger(DBFactory.class);

    private static String CLASSNAME;

    private static String JDBC_URL;

    private static String USERNAME;

    private static String PASSWORD;

    private static String CACHE_PREP_STMTS;

    private static HikariDataSource ds;

    private HikariConfig config;

    public DBFactory() {

    InputStream inputStream;

    config = new HikariConfig();

        String resource = "db.properties";

        Properties properties = new Properties();

        try {

        inputStream = getClass().getClassLoader().getResourceAsStream(resource);

            properties.load(inputStream);

            System.out.println("jdbcurl:" + properties.getProperty("jdbcUrl"));

            System.out.println("className" + properties.getProperty("dataSourceClassName"));

            CLASSNAME = properties.getProperty("dataSourceClassName");

            JDBC_URL = properties.getProperty("jdbcUrl");

            USERNAME = properties.getProperty("dataSource.user");

            PASSWORD = properties.getProperty("dataSource.password");

            CACHE_PREP_STMTS = properties.getProperty("cachePrepStmts");

            config.setDriverClassName(CLASSNAME);

            config.setJdbcUrl( JDBC_URL );

            config.setUsername( USERNAME );

            config.setPassword( PASSWORD );

            config.addDataSourceProperty( "cachePrepStmts" , CACHE_PREP_STMTS );

            config.addDataSourceProperty( "prepStmtCacheSize" , "250" );

            config.addDataSourceProperty( "prepStmtCacheSqlLimit" , "2048" );

            ds = new HikariDataSource( config );

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

    public Connection getConnection() throws SQLException {

    /*

        try(Connection con = ds.getConnection()){

            System.out.println("연결상태확인:" + con);

            String sql = "SELECT * from board where id > 4 and id < 10";

            PreparedStatement pstmt = con.prepareStatement(sql);

            ResultSet rs = pstmt.executeQuery();

            while (rs.next()) {

                System.out.println("진짜 연결되었는가:" + rs.getString(2));

            }

        }

        catch(Exception e) {

        System.out.println("연결실패확인:" + e.getMessage());

        }

    */

        return ds.getConnection();

    }

    public void close(Connection conn, PreparedStatement ps, ResultSet rs) {

if ( rs != null ) {

try {

rs.close();

}

catch(Exception ex) {

System.out.println("오류 발생: " + ex);

}

close(conn, ps); // Recursive 구조 응용(재귀 함수)

} // end of if

}

public void close(Connection conn, PreparedStatement ps) {

if (ps != null ) {

try {

ps.close();

}

catch(Exception ex) {

System.out.println("오류 발생: " + ex);

}

} // end of if

if (conn != null ) {

try {

conn.close();

}

catch(Exception ex) {

System.out.println("오류 발생: " + ex);

}

} // end of if

}

}

1. [JSP] 17. JSP/Servlet MVC2 - 페이징네이션과 검색 그리고 오라클 프로젝트 (2), 2020-09-30

https://yyman.tistory.com/1429