init

.gitignore

@@ -0,0 +1,36 @@
+HELP.md
+.gradle
+build/
+target/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+.DS_Store
+deploy/app.jar

build.gradle

@@ -0,0 +1,39 @@
+plugins {
+	id 'org.springframework.boot' version '2.3.0.RELEASE'
+	id 'io.spring.dependency-management' version '1.0.9.RELEASE'
+	id 'java'
+	id 'org.asciidoctor.convert' version '1.5.6'
+}
+
+group = 'com.aionnect'
+version = '0.0.1'
+sourceCompatibility = '1.8'
+
+asciidoctor {
+	sourceDir 'src/main/asciidoc'
+	attributes 'snippets': file('target/snippets')
+}
+
+repositories {
+	maven { url 'https://maven.aliyun.com/repository/google' }
+	maven { url 'https://maven.aliyun.com/repository/jcenter' }
+	maven { url 'http://maven.aliyun.com/nexus/content/groups/public' }
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-thymeleaf'
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	implementation 'org.springframework.boot:spring-boot-starter-security'
+	implementation 'org.springframework.security:spring-security-test'
+	implementation 'io.jsonwebtoken:jjwt:0.9.1'
+	testImplementation 'junit:junit'
+	testImplementation 'org.springframework.restdocs:spring-restdocs-mockmvc'
+	testImplementation('org.springframework.boot:spring-boot-starter-test') {
+		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
+	}
+}
+
+test {
+	useJUnitPlatform()
+}

deploy/Dockerfile

@@ -0,0 +1,6 @@
+FROM openjdk:8-jdk-alpine
+COPY *.jar .
+
+ENV SPRING_PROFILES_ACTIVE prod
+EXPOSE 8080
+ENTRYPOINT ["java","-jar","/app.jar"]

deploy/build.sh

@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+
+registry_host="ccr.ccs.tencentyun.com/aionnect"
+project_name="hello-java"
+
+cd ..
+
+./gradlew build
+cp -r build/libs/*.jar deploy/app.jar
+
+for item in $(docker images | grep -E "$registry_host/$project_name\s+\S*" -o);
+do
+    if [[ $item != "$registry_host/$project_name" ]];
+    then
+        echo "remove $registry_host/$project_name:$item"
+        docker rmi "$registry_host/$project_name:$item"
+    fi
+done
+
+tag=$(date +%s)
+docker build --no-cache --disable-content-trust=true -t $registry_host/$project_name:$tag ./deploy
+
+#docker push $registry_host/$project_name:$tag

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Fri May 22 19:44:06 CST 2020
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.3-all.zip
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStorePath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME

gradlew

@@ -0,0 +1,183 @@
+#!/usr/bin/env sh
+
+#
+# Copyright 2015 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"

gradlew.bat

@@ -0,0 +1,103 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'helloJava'

src/main/asciidoc/index.adoc

@@ -0,0 +1,17 @@
+= HelloJava接口文档
+
+此文档由WebMvc和asciidoc自动生成，服务默认host http://localhost:8080
+
+=== 测试API
+
+.request
+include::{snippets}/greeting/curl-request.adoc[]
+request parameters
+include::{snippets}/greeting/request-parameters.adoc[]
+
+.response
+response body
+include::{snippets}/greeting/response-body.adoc[]
+include::{snippets}/greeting/response-fields.adoc[]
+
+As you can see the format is very simple, and in fact you always get the same message.

src/main/java/com/aionnect/helloJava/HelloJavaApplication.java

@@ -0,0 +1,29 @@
+package com.aionnect.helloJava;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+import org.springframework.web.servlet.config.annotation.CorsRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+
+@SpringBootApplication
+public class HelloJavaApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(HelloJavaApplication.class, args);
+    }
+
+    @Bean
+    public WebMvcConfigurer corsConfigurer() {
+        return new WebMvcConfigurer() {
+            @Override
+            public void addCorsMappings(CorsRegistry registry) {
+                registry.addMapping("/**")
+                        .allowedOrigins("*")
+                        .allowedMethods("GET", "POST", "DELETE", "PUT", "OPTIONS", "HEAD")
+                        .allowedHeaders("Origin", "x-requested-with", "Content-Type", "Accept", "Authorization")
+                        .maxAge(3600);
+            }
+        };
+    }
+}

src/main/java/com/aionnect/helloJava/JWTAuthorizationFilter.java

@@ -0,0 +1,61 @@
+package com.aionnect.helloJava;
+
+import io.jsonwebtoken.Jwts;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.web.authentication.www.BasicAuthenticationFilter;
+
+import javax.servlet.FilterChain;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.ArrayList;
+
+/**
+ * token的校验
+ */
+public class JWTAuthorizationFilter extends BasicAuthenticationFilter {
+
+    public JWTAuthorizationFilter(AuthenticationManager authenticationManager) {
+        super(authenticationManager);
+    }
+
+    // 从Authorization请求头读取token数据，然后用校验token的合法性
+    // 如果校验通过，就认为这是一个取得授权的合法请求
+    // /login或配置放行的请求路径，不校验
+    @Override
+    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException {
+        String header = request.getHeader("Authorization");
+
+        if (null == header || !header.startsWith("Bearer ")) {
+            chain.doFilter(request, response);
+            return;
+        }
+
+        UsernamePasswordAuthenticationToken authentication = getAuthentication(request);
+
+        SecurityContextHolder.getContext().setAuthentication(authentication);
+        chain.doFilter(request, response);
+    }
+
+    private UsernamePasswordAuthenticationToken getAuthentication(HttpServletRequest request) {
+        String token = request.getHeader("Authorization");
+        if (null != token) {
+            // parse the token.
+            String user = Jwts.parser()
+                    .setSigningKey("*(#U%TUJF#32")
+                    .parseClaimsJws(token.replace("Bearer ", ""))
+                    .getBody()
+                    .getSubject();
+
+            if (null != user) {
+                return new UsernamePasswordAuthenticationToken(user, null, new ArrayList<>());
+            }
+            return null;
+        }
+        return null;
+    }
+
+}

src/main/java/com/aionnect/helloJava/JWTLoginFilter.java

@@ -0,0 +1,103 @@
+package com.aionnect.helloJava;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.jsonwebtoken.Jwts;
+import io.jsonwebtoken.SignatureAlgorithm;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+import javax.servlet.FilterChain;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Date;
+
+/**
+ * 从请求中解析用户名密码，经过userDetailsService验证正确后，生成一个token，并将token返回给客户端
+ */
+public class JWTLoginFilter extends UsernamePasswordAuthenticationFilter {
+    private final AuthenticationManager authenticationManager;
+
+    public JWTLoginFilter(AuthenticationManager authenticationManager) {
+        this.authenticationManager = authenticationManager;
+    }
+
+    static class JWTUser {
+        private String username;
+        private String password;
+
+        public String getUsername() {
+            return username;
+        }
+
+        public void setUsername(String username) {
+            this.username = username;
+        }
+
+        public String getPassword() {
+            return password;
+        }
+
+        public void setPassword(String password) {
+            this.password = password;
+        }
+    }
+
+    // 接收并解析用户凭证
+    // 默认POST login会进入此方法
+    @Override
+    public Authentication attemptAuthentication(HttpServletRequest req, HttpServletResponse res)
+            throws AuthenticationException {
+        JWTUser user = null;
+        try {
+            user = new ObjectMapper()
+                    .readValue(req.getInputStream(), JWTUser.class);
+        } catch (Exception ignored) {}
+
+        if (null == user || null == user.getUsername() || user.getUsername().isEmpty()) {
+            String username = req.getParameter("username");
+            String password = req.getParameter("password");
+            if (null != username && !username.isEmpty()) {
+                if (null == user) {
+                    user = new JWTUser();
+                }
+                user.setUsername(username);
+                if ((null == user.getPassword() || user.getPassword().isEmpty()) && !password.isEmpty()) {
+                    user.setPassword(password);
+                }
+            }
+        }
+        if (null == user || user.getUsername().isEmpty()) {
+            throw new RuntimeException("Username can not be empty");
+        }
+
+        return authenticationManager.authenticate(
+                new UsernamePasswordAuthenticationToken(
+                        user.getUsername(),
+                        user.getPassword(),
+                        new ArrayList<>())
+        );
+    }
+
+    // 用户成功登录后被调用，生成token
+    @Override
+    protected void successfulAuthentication(HttpServletRequest req,
+                                            HttpServletResponse res,
+                                            FilterChain chain,
+                                            Authentication auth) throws IOException, ServletException {
+
+        org.springframework.security.core.userdetails.User user =
+                (org.springframework.security.core.userdetails.User) auth.getPrincipal();
+        String token = Jwts.builder()
+                .setSubject(user.getUsername())
+                .setExpiration(new Date(System.currentTimeMillis() + 60 * 60 * 24 * 1000))
+                .signWith(SignatureAlgorithm.HS512, "*(#U%TUJF#32")
+                .compact();
+        res.addHeader("Authorization", "Bearer " + token);
+    }
+}

src/main/java/com/aionnect/helloJava/WebSecurityConfig.java

@@ -0,0 +1,40 @@
+package com.aionnect.helloJava;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+import org.springframework.security.core.userdetails.User;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.provisioning.InMemoryUserDetailsManager;
+
+@Configuration
+@EnableWebSecurity
+public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
+    @Override
+    protected void configure(HttpSecurity http) throws Exception {
+        http.cors().and().csrf().disable().authorizeRequests()
+                .antMatchers("/", "/home", "/greeting").permitAll() // 放行不做安全校验的path，/login不用加入默认放行
+                .anyRequest().authenticated()
+                .and()
+                .addFilter(new JWTLoginFilter(authenticationManager()))
+                .addFilter(new JWTAuthorizationFilter(authenticationManager()));
+    }
+
+    // userDetailsService对JWTLoginFilter.attemptAuthentication()的解析结果进行验证
+    // 验证通过进入JWTLoginFilter.successfulAuthentication()
+    @Bean
+    @Override
+    public UserDetailsService userDetailsService() {
+        UserDetails user =
+                User.withDefaultPasswordEncoder()
+                        .username("user")
+                        .password("password")
+                        .roles("USER")
+                        .build();
+
+        return new InMemoryUserDetailsManager(user);
+    }
+}

src/main/java/com/aionnect/helloJava/controller/GreetingController.java

@@ -0,0 +1,20 @@
+package com.aionnect.helloJava.controller;
+
+import com.aionnect.helloJava.entity.Greeting;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+@RestController
+public class GreetingController {
+
+    private static final String template = "Hello, %s!";
+    private final AtomicLong counter = new AtomicLong();
+
+    @GetMapping("/greeting")
+    public Greeting greeting(@RequestParam(value = "name", defaultValue = "World") String name) {
+        return new Greeting(counter.incrementAndGet(), String.format(template, name));
+    }
+}

src/main/java/com/aionnect/helloJava/controller/HomeController.java

@@ -0,0 +1,13 @@
+package com.aionnect.helloJava.controller;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+
+@Controller
+public class HomeController {
+
+    @GetMapping(value = {"/", "home"})
+    public String home() {
+        return "home";
+    }
+}

src/main/java/com/aionnect/helloJava/entity/Greeting.java

@@ -0,0 +1,20 @@
+package com.aionnect.helloJava.entity;
+
+public class Greeting {
+
+    private final long id;
+    private final String content;
+
+    public Greeting(long id, String content) {
+        this.id = id;
+        this.content = content;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public String getContent() {
+        return content;
+    }
+}

src/main/resources/templates/home.html

@@ -0,0 +1,9 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="https://www.thymeleaf.org" xmlns:sec="https://www.thymeleaf.org/thymeleaf-extras-springsecurity3" lang="en">
+<head>
+    <title>Hello Java</title>
+</head>
+<body>
+<h1>Welcome!</h1>
+</body>
+</html>

src/test/java/com/aionnect/helloJava/HelloJavaApplicationTests.java

@@ -0,0 +1,13 @@
+package com.aionnect.helloJava;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class HelloJavaApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}

src/test/java/com/aionnect/helloJava/WebLayerTest.java

@@ -0,0 +1,48 @@
+package com.aionnect.helloJava;
+
+import com.aionnect.helloJava.controller.GreetingController;
+import org.junit.jupiter.api.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.restdocs.AutoConfigureRestDocs;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.servlet.MockMvc;
+
+import static org.hamcrest.Matchers.containsString;
+import static org.springframework.restdocs.mockmvc.MockMvcRestDocumentation.document;
+import static org.springframework.restdocs.payload.PayloadDocumentation.*;
+import static org.springframework.restdocs.request.RequestDocumentation.*;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@RunWith(SpringRunner.class)
+@WebMvcTest(GreetingController.class)
+@AutoConfigureRestDocs(outputDir = "target/snippets")
+public class WebLayerTest {
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Test
+    public void shouldReturnDefaultMessage() throws Exception {
+        // refer to:
+        // https://docs.spring.io/spring-restdocs/docs/current/reference/html5/
+        // https://asciidoctor.org/docs/asciidoctor-gradle-plugin/
+        this.mockMvc.perform(get("/greeting").queryParam("name", "World"))
+                .andDo(print())
+                .andExpect(status().isOk())
+                .andExpect(content().string(containsString("Hello, World")))
+                .andDo(document("greeting",
+                        requestParameters(
+                                parameterWithName("name").description("姓名")
+                        ),
+                        responseFields(
+                                fieldWithPath("id").description("ID"),
+                                fieldWithPath("content").description("欢迎语")
+                        )
+                ));
+    }
+}

test.html

@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <title>Hello CORS</title>
+    <script src="http://code.jquery.com/jquery-3.5.1.min.js"
+            integrity="sha256-9/aliU8dGd2tb6OSsuzixeV4y/faTqgFtohetphbbj0="
+            crossorigin="anonymous"></script>
+</head>
+
+<body>
+<div>
+    <p class="greeting-id">The ID is </p>
+    <p class="greeting-content">The content is </p>
+</div>
+<script>
+    $(document).ready(function() {
+        $.ajax({
+            url: "http://localhost:8080/greeting"
+        }).then(function(data, status, jqxhr) {
+            $('.greeting-id').append(data.id);
+            $('.greeting-content').append(data.content);
+            console.log(jqxhr);
+        });
+    });
+</script>
+</body>
+</html>