add example

examples/chapter05/spring-boot-web-demo/settings.gradle

@@ -1,2 +1,2 @@
-rootProject.name = 'spring-boot-application'
+rootProject.name = 'spring-boot-web-demo'
 

examples/chapter06/spring-boot-jpa-demo/.gitignore

@@ -0,0 +1,42 @@
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### IntelliJ IDEA ###
+.idea/modules.xml
+.idea/jarRepositories.xml
+.idea/compiler.xml
+.idea/libraries/
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store

examples/chapter06/spring-boot-jpa-demo/build.gradle

@@ -0,0 +1,35 @@
+plugins {
+    id 'java'
+    id 'org.springframework.boot' version '3.3.5'
+    id 'io.spring.dependency-management' version '1.1.6'
+}
+
+group = 'com.lk.demo'
+version = '1.0-SNAPSHOT'
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(17)
+    }
+}
+
+repositories {
+    mavenLocal()
+    maven { url 'https://mirrors.cloud.tencent.com/nexus/repository/maven-public/' }
+    maven { url 'https://maven.aliyun.com/repository/central' }
+    maven { url 'https://maven.aliyun.com/repository/public' }
+    mavenCentral()
+}
+
+dependencies {
+    implementation 'org.springframework.boot:spring-boot-starter-web'
+    runtimeOnly 'com.mysql:mysql-connector-j'
+    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
+    testImplementation platform('org.junit:junit-bom:5.10.0')
+    testImplementation 'org.junit.jupiter:junit-jupiter'
+}
+
+test {
+    useJUnitPlatform()
+}
+

examples/chapter06/spring-boot-jpa-demo/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Sat Oct 26 17:29:35 CST 2024
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.8-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

examples/chapter06/spring-boot-jpa-demo/gradlew

@@ -0,0 +1,234 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original 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 POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | 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" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"

examples/chapter06/spring-boot-jpa-demo/gradlew.bat

@@ -0,0 +1,89 @@
+@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 execute
+
+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 execute
+
+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
+
+: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 %*
+
+: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

examples/chapter06/spring-boot-jpa-demo/settings.gradle

@@ -0,0 +1,2 @@
+rootProject.name = 'spring-boot-jpa-demo'
+

examples/chapter06/spring-boot-jpa-demo/src/main/java/com/lk/demo/JdbcCrudExample.java

@@ -0,0 +1,107 @@
+package com.lk.demo;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+public class JdbcCrudExample {
+
+    private static final String DB_URL = "jdbc:mysql://localhost:3306/paopao";
+    private static final String USER = "root";
+    private static final String PASS = "root";
+
+    public static void main(String[] args) {
+        Connection conn = null;
+        try {
+            // 加载MySQL驱动
+            Class.forName("com.mysql.cj.jdbc.Driver");
+
+            // 获取数据库连接
+            conn = DriverManager.getConnection(DB_URL, USER, PASS);
+
+            // 创建表
+            createTable(conn);
+
+            // 插入记录
+            insertUser(conn, "Alice", 28);
+            insertUser(conn, "Bob", 32);
+
+            // 查询记录
+            queryUsers(conn);
+
+            // 更新记录
+            updateUser(conn, "Alice", 29);
+
+            // 删除记录
+            deleteUser(conn, "Bob");
+
+            // 再次查询记录
+            queryUsers(conn);
+
+        } catch (ClassNotFoundException | SQLException e) {
+            e.printStackTrace();
+        } finally {
+            if (conn != null) {
+                try {
+                    conn.close();
+                } catch (SQLException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+    }
+
+    private static void createTable(Connection conn) throws SQLException {
+        String sql = "CREATE TABLE IF NOT EXISTS users (" +
+                "id INT AUTO_INCREMENT PRIMARY KEY," +
+                "name VARCHAR(255) NOT NULL," +
+                "age INT)";
+        PreparedStatement stmt = conn.prepareStatement(sql);
+        stmt.executeUpdate();
+        stmt.close();
+    }
+
+    private static void insertUser(Connection conn, String name, int age) throws SQLException {
+        String sql = "INSERT INTO users (name, age) VALUES (?, ?)";
+        PreparedStatement pstmt = conn.prepareStatement(sql);
+        pstmt.setString(1, name);
+        pstmt.setInt(2, age);
+        pstmt.executeUpdate();
+        pstmt.close();
+    }
+
+    private static void queryUsers(Connection conn) throws SQLException {
+        String sql = "SELECT * FROM users";
+        PreparedStatement pstmt = conn.prepareStatement(sql);
+        ResultSet rs = pstmt.executeQuery();
+        while (rs.next()) {
+            int id = rs.getInt("id");
+            String name = rs.getString("name");
+            int age = rs.getInt("age");
+            System.out.println("ID: " + id + ", Name: " + name + ", Age: " + age);
+        }
+        rs.close();
+        pstmt.close();
+    }
+
+    private static void updateUser(Connection conn, String name, int age) throws SQLException {
+        String sql = "UPDATE users SET age = ? WHERE name = ?";
+        PreparedStatement pstmt = conn.prepareStatement(sql);
+        pstmt.setInt(1, age);
+        pstmt.setString(2, name);
+        int rowsUpdated = pstmt.executeUpdate();
+        System.out.println(rowsUpdated + " row(s) updated.");
+        pstmt.close();
+    }
+
+    private static void deleteUser(Connection conn, String name) throws SQLException {
+        String sql = "DELETE FROM users WHERE name = ?";
+        PreparedStatement pstmt = conn.prepareStatement(sql);
+        pstmt.setString(1, name);
+        int rowsDeleted = pstmt.executeUpdate();
+        System.out.println(rowsDeleted + " row(s) deleted.");
+        pstmt.close();
+    }
+}

examples/chapter06/spring-boot-jpa-demo/src/main/java/com/lk/demo/MyWebApplication.java

@@ -0,0 +1,16 @@
+package com.lk.demo;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.AutoConfiguration;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+
+@SpringBootApplication
+public class MyWebApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(MyWebApplication.class, args);
+    }
+
+}

examples/chapter06/spring-boot-jpa-demo/src/main/java/com/lk/demo/User.java

@@ -0,0 +1,58 @@
+package com.lk.demo;
+
+public class User {
+    private Long id;
+    private String name;
+    private String password;
+    private String email;
+    private String phone;
+    private Integer age;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public String getPhone() {
+        return phone;
+    }
+
+    public void setPhone(String phone) {
+        this.phone = phone;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public Integer getAge() {
+        return age;
+    }
+
+    public void setAge(Integer age) {
+        this.age = age;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    public void setPassword(String password) {
+        this.password = password;
+    }
+}

examples/chapter06/spring-boot-jpa-demo/src/main/java/com/lk/demo/UserController.java

@@ -0,0 +1,92 @@
+package com.lk.demo;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@RestController
+@RequestMapping("/users")
+public class UserController {
+
+    @Autowired
+    UserService userService;
+    /**
+     * 获取指定ID的用户信息
+     * Method: GET
+     * URL: /users/{id}
+     * 输入参数:
+     *   - @PathVariable Long id: 用户ID
+     * 返回数据结构:
+     *   - User对象，包含id, name, age
+     */
+    @GetMapping("/{id}")
+    public User getUser(@PathVariable Long id){
+        System.out.println("Got id from http request: " + id);
+        return userService.getUser(id);
+    }
+
+    /**
+     * 根据名称分页查询用户列表
+     * Method: GET
+     * URL: /users?name={name}&page={page}&pageSize={pageSize}
+     * 输入参数:
+     *   - @RequestParam String name: 用户名称
+     *   - @RequestParam int page: 当前页码
+     *   - @RequestParam int pageSize: 每页大小
+     * 返回数据结构:
+     *   - List<User> 用户列表，每个User对象包含id, name, age
+     */
+    @GetMapping("")
+    public List<User> findUsers(@RequestParam("name") String name, @RequestParam int page, @RequestParam int pageSize){
+        System.out.println("Got name: " + name+ " page: " + page+ " pageSize: " + pageSize);
+        return userService.queryUsers();
+    }
+
+    /**
+     * 创建新用户
+     * Method: POST
+     * URL: /users
+     * 输入参数:
+     *   - @RequestBody User user: 用户对象，包含name, age, password,email
+     * 返回数据结构:
+     *   - User对象，包含id, name, age, password,email
+     */
+    @PostMapping
+    public User createUser(@RequestBody User user){
+        System.out.println("Got name: "+user.getName()+ "pass:" +user.getPassword());
+        return userService.createUser(user);
+    }
+
+    /**
+     * 更新指定ID的用户信息
+     * Method: PUT
+     * URL: /users/{id}
+     * 输入参数:
+     *   - @PathVariable Long id: 用户ID
+     *   - @RequestBody User user: 用户对象，包含name, age, password
+     * 返回数据结构:
+     *   - User对象，包含id, name, age, password
+     */
+    @PutMapping("/{id}")
+    public User updateUser(@PathVariable Long id, @RequestBody User user){
+        System.out.println("Got id: "+id+ "name: "+user.getName()+  " pass:" +user.getPassword()+" age: "+user.getAge());
+        return userService.updateUser(id, user);
+    }
+
+    /**
+     * 删除指定ID的用户
+     * Method: DELETE
+     * URL: /users/{id}
+     * 输入参数:
+     *   - @PathVariable Long id: 用户ID
+     * 返回数据结构:
+     *   - String "ok" 表示删除成功
+     */
+    @DeleteMapping("/{id}")
+    public String deleteUser(@PathVariable Long id){
+        System.out.println("delete id: "+id);
+        return "ok";
+    }
+}

examples/chapter06/spring-boot-jpa-demo/src/main/java/com/lk/demo/UserService.java

@@ -0,0 +1,48 @@
+package com.lk.demo;
+
+import org.springframework.stereotype.Service;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestBody;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Service
+public class UserService {
+
+    public User getUser(Long id){
+        User user = new User();
+        user.setId(id);
+        user.setName("lk");
+        user.setAge(18);
+        return user;
+    }
+
+
+    public List<User> queryUsers(){
+       List<User> users = new ArrayList<>();
+       User u1 = new User();
+       u1.setName("John");
+       u1.setEmail("john@gmail.com");
+       u1.setPhone("123456789");
+       users.add(u1);
+       User u2 = new User();
+       u2.setName("Mike");
+       u2.setEmail("mike@gmail.com");
+       u2.setPhone("123456789");
+       users.add(u2);
+       return users;
+    }
+
+
+    public User createUser(User user){
+        user.setId(22L);
+        return user;
+    }
+
+    public User updateUser(Long id, User user){
+        user.setId(id);
+        return user;
+    }
+
+}

examples/chapter06/spring-boot-jpa-demo/src/main/resources/application.yml

@@ -0,0 +1,16 @@
+spring:
+  jackson:
+    property-naming-strategy: SNAKE_CASE # 驼峰转下划线
+  datasource:
+    url: jdbc:mysql://localhost:3306/paopao?useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true # MySQL连接URL，paopao是数据库名
+    driverClassName: com.mysql.cj.jdbc.Driver # MySQL的Driver类名
+    username: root # MySQL用户名
+    password: root # MySQL密码
+  jpa:
+    show-sql: true
+    open-in-view: false
+    defer-datasource-initialization: true
+    database-platform: org.hibernate.dialect.MySQL8Dialect # 修改为MySQL的Dialect
+    hibernate:
+      ddl-auto: update # 根据需要调整，update适用于开发和某些生产环境
+      format_sql: true # 保持原样，用于格式化SQL输出