Servlet_서블릿 매핑 xml 파일로 작성하여 브라우저 요청하기

- servlet

--- servlet-api

1) 프로젝트 우클릭 > Build Path > Classpath

    - Add External JARs... > servlet-api.jar 파일 추가하기 

 

- 브라우저에서 요청하는 기본적인 방법

http:// [ IP주소 ] : [ 포트 번호 ] / [ 프로젝트 이름 ] / [ 패키지 이름이 포함된 클래스 이름 ]

 

서블릿 매핑 > web.xml 파일에 설정합니다.

<servlet>
	<servlet-name> [ servlet-mapping에서 설정한 servlet-name ]</servlet-name>
    <servlet-class> [ 실제 기능을 수행하는 클래스 경로 ] </servlet-class>
</servlet>

<servlet-mapping>
	<servlet-name> [ 서블릿 이름 ] </servlet-name>
    <url-pattern> [ 웹 브라우저에서 요청하는 이름 ] </url-pattern>
</servlet-mapping>

 

>>>

http:// [ IP 주소 ] / [ 프로젝트 이름 ] / [웹 브라우저에서 요청하는 이름]

 

- 주의사항 : 여러 개의 서블릿 매핑을 진행하는 경우 servlet끼리 위치시킵니다.

- 서블릿은 메모리에 존재하는 서블릿을 재사용함으로 빠르고 효율적으로 동작합니다.

- 서블릿 클래스 : HttpServlet 상속

 

2) 어노테이션으로 매핑하기

@WebServlet(" / [ 웹 브라우저에서 요청하는 이름 ] ") : 서블릿 클래스 위에 선언합니다.

 

- 주의사항 : 어노테이션으로 매핑하는 경우 반드시 HttpServlet을 상속받아야 합니다.

 

- 주의사항 : web.xml 파일에서 설정한 매핑 이름과 어노테이션으로 설정한 매핑 이름이 동일한 경우 오류 발생

A child container failed during start

ExecutionException 

 

 

===== 실습 =====

1. New > Spring Legacy Project 생성

--- Project Name : servletProject

--- Template : Spring MVC Project

 

--- package : com.basic.servlet

 

 

2. Java 버전 변경

프로젝트 우클릭 > Properties > Project Facet 

 

 

3. pom.xml 파일 수정

<?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.basic</groupId>
    <artifactId>servlet</artifactId>
    <name>servletProject</name>
    <packaging>war</packaging>
    <version>1.0.0-BUILD-SNAPSHOT</version>
    <properties>
        <java-version>11</java-version>
        <org.springframework-version>5.3.27</org.springframework-version>
        <org.aspectj-version>1.9.19</org.aspectj-version>
        <org.slf4j-version>2.0.7</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 -->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</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 -->
<!-- Servlet : 기본값
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.1</version>
            <scope>provided</scope>
        </dependency>
-->
<!-- javax.servlet-api : servlet-api 대신 사용 -->
        <!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.0</version>
            <scope>provided</scope>
        </dependency>
        
<!-- javax.servlet.jsp-api : jsp-api 대신 사용 -->
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>javax.servlet.jsp-api</artifactId>
            <version>2.3.3</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>4.13.2</version>
            <scope>test</scope>
        </dependency>       
    <!-- project 기본 설정 끝 -->
         
    </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>
 
<!-- maven-compiler-plugin : 버전 변경 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.10.1</version>
                <configuration>
                    <source>11</source>
                    <target>11</target>
                    <compilerArgument>-Xlint:all</compilerArgument>
                    <showWarnings>true</showWarnings>
                    <showDeprecation>true</showDeprecation>
                </configuration>
            </plugin>
            
<!-- exec-maven-plugin : 버전 변경 -->
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>3.1.0</version>
                <configuration>
                    <mainClass>org.test.int1.Main</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>
 

 

 

4. src > main > webapp > WEB-INF > web.xml 파일에 서블릿 매핑하기

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee https://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
 
    <!-- 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>
 
    <servlet>
        <servlet-name>userServlet</servlet-name>
        <servlet-class>com.basic.servlet.UserServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>userServlet</servlet-name>
        <url-pattern>/user</url-pattern>
    </servlet-mapping>
</web-app>

 

 

5. UserServlet 클래스 생성

package com.basic.servlet;
 
import java.io.IOException;
import java.io.PrintWriter;
 
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
public class UserServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
 
    @Override
    public void init() throws ServletException{
        System.out.println("[ UserServlet ] : init()");
    }
    
    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        System.out.println("[ UserServlet ] : doGet()");
        
        // 브라우저 화면에 출력하기
        PrintWriter out = response.getWriter();
        
        out.print("<html>");
        out.print("<body>");
        out.print("<h1>Hello!</h1>");
        out.print("<h3>UserServlet!</h3>");
        out.print("</body>");
        out.print("</html>");
    }
    
    @Override
    public void destroy() {
        System.out.println("[ UserServlet ] : destroy()");
    }
}
 

 

6. 실행하기

Run As > Run on Server

> 웹 브라우저에 "localhost:8080/servlet/user" 입력