Java SpringBoot实现带界面的代码生成器详解

server.port=8080

spring.datasource.url=jdbc:mysql://localhost:3306/demo?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai

spring.datasource.username=root

spring.datasource.password=root

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

< project xmlns = "http://maven.apache.org/POM/4.0.0" xmlns:xsi = "http://HdhCmsTestw3.org/2001/XMLSchema-instance"

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

     < modelVersion >4.0.0</ modelVersion >

     < parent >

         < groupId >org.springframework.boot</ groupId >

         < artifactId >spring-boot-starter-parent</ artifactId >

         < version >2.5.4</ version >

         < relativePath /> <!-- lookup parent from repository -->

     </ parent >

     < groupId >com.yl</ groupId >

     < artifactId >generate_code</ artifactId >

     < version >0.0.1-SNAPSHOT</ version >

     < name >generate_code</ name >

     < description >Demo project for Spring Boot</ description >

     < properties >

         < java.version >1.8</ java.version >

     </ properties >

     < dependencies >

         < dependency >

             < groupId >org.springframework.boot</ groupId >

             < artifactId >spring-boot-starter-freemarker</ artifactId >

         </ dependency >

         < dependency >

             < groupId >org.springframework.boot</ groupId >

             < artifactId >spring-boot-starter-web</ artifactId >

         </ dependency >

         < dependency >

             < groupId >mysql</ groupId >

             < artifactId >mysql-connector-java</ artifactId >

             < scope >runtime</ scope >

         </ dependency >

         < dependency >

             < groupId >org.springframework.boot</ groupId >

             < artifactId >spring-boot-starter-test</ artifactId >

             < scope >test</ scope >

         </ dependency >

         < dependency >

             < groupId >com.google.guava</ groupId >

             < artifactId >guava</ artifactId >

             < version >30.1-jre</ version >

         </ dependency >

     </ dependencies >

     < build >

         < plugins >

             < plugin >

                 < groupId >org.springframework.boot</ groupId >

                 < artifactId >spring-boot-maven-plugin</ artifactId >

             </ plugin >

         </ plugins >

     </ build >

</ project >

package com.yl.generate_code.utils;

import org.springframework.web.servlet.config.annotation.CorsRegistry;

import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

public class CORFSConfiguration extends WebMvcConfigurerAdapter {

     @Override

     public void addCorsMappings(CorsRegistry registry) {

         //所有请求都允许跨域

         registry.addMapping( "/**" )

                 .allowedOrigins( "*" )

                 .allowedMethods( "*" )

                 .allowedHeaders( "*" );

     }

}

package com.yl.generate_code.utils;

import com.yl.generate_code.model.Db;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

public class DBUtils {

     private static Connection connection;

     public static Connection getConnection() {

         return connection;

     }

     public static Connection init(Db db) {

         if (connection == null ) {

             try {

                 Class.forName( "com.mysql.cj.jdbc.Driver" );

                 connection = DriverManager.getConnection( db.getUrl(),db.getUsername(), db.getPassword());

             } catch (ClassNotFoundException e) {

                 e.printStackTrace();

             } catch (SQLException e) {

                 e.printStackTrace();

             }

         }

         return connection;

     }

}

package ${packetName}.model;

import java.util.Date;

/**

* @Description: ${modelName}实体类

* @Author: wfj

* @CreateDate ${createDate}

* @Version: 1.0V

*/

public class ${modelName} {

     <# if columns??>

         <#list columns as column>

             <# if column.type= 'VARCHAR' || column.type= 'TEXT' || column.type= 'CHAR' >

                 /**

                 * ${column.remark}

                 */

                 private String ${column.propertyName?uncap_first};

             </# if >

             <# if column.type= 'INT' >

                 /**

                 * ${column.remark}

                 */

                 private Integer ${column.propertyName?uncap_first};

             </# if >

             <# if column.type= 'DATETIME' >

                 /**

                 * ${column.remark}

                 */

                 private Date ${column.propertyName?uncap_first};

             </# if >

             <# if column.type= 'BIGINT' >

                 /**

                 * ${column.remark}

                 */

                 private Long ${column.propertyName?uncap_first};

             </# if >

             <# if column.type= 'DOUBLE' >

                 /**

                 * ${column.remark}

                 */

                 private Double ${column.propertyName?uncap_first};

             </# if >

             <# if column.type= 'BIT' >

                 /**

                 * ${column.remark}

                 */

                 private Boolean ${column.propertyName?uncap_first};

             </# if >

         </#list>

         <#list columns as column>

             <# if column.type= 'VARCHAR' || column.type= 'TEXT' || column.type= 'CHAR' >

                public String get${column.propertyName}() {

                     return ${column.propertyName?uncap_first};

                 }

                 public void set${column.propertyName}(String ${column.propertyName?uncap_first}) {

                     this .${column.propertyName?uncap_first} = ${column.propertyName?uncap_first};

                 }

             </# if >

             <# if column.type= 'INT' >

                 public Integer get${column.propertyName}() {

                 return ${column.propertyName?uncap_first};

                 }

                 public void set${column.propertyName}(Integer ${column.propertyName?uncap_first}) {

                 this .${column.propertyName?uncap_first} = ${column.propertyName?uncap_first};

                 }

             </# if >

             <# if column.type= 'DATETIME' >

                 public Date get${column.propertyName}() {

                 return ${column.propertyName?uncap_first};

                 }

                 public void set${column.propertyName}(Date ${column.propertyName?uncap_first}) {

                 this .${column.propertyName?uncap_first} = ${column.propertyName?uncap_first};

                 }

             </# if >

             <# if column.type= 'BIGINT' >

                 public Long get${column.propertyName}() {

                 return ${column.propertyName?uncap_first};

                 }

                 public void set${column.propertyName}(Long ${column.propertyName?uncap_first}) {

                 this .${column.propertyName?uncap_first} = ${column.propertyName?uncap_first};

                 }

             </# if >

             <# if column.type= 'DOUBLE' >

                 public Double get${column.propertyName}() {

                 return ${column.propertyName?uncap_first};

                 }

                 public void set${column.propertyName}(Double ${column.propertyName?uncap_first}) {

                 this .${column.propertyName?uncap_first} = ${column.propertyName?uncap_first};

                 }

             </# if >

             <# if column.type= 'BIT' >

                 public Boolean get${column.propertyName}() {

                 return ${column.propertyName?uncap_first};

                 }

                 public void set${column.propertyName}(Boolean ${column.propertyName?uncap_first}) {

                 this .${column.propertyName?uncap_first} = ${column.propertyName?uncap_first};

                 }

             </# if >

         </#list>

     </# if >

}

package com.yl.generate_code.controller;

import com.google测试数据mon.base.CaseFormat;

import com.yl.generate_code.model.Db;

import com.yl.generate_code.model.ResultModel;

import com.yl.generate_code.model.TableClass;

import com.yl.generate_code.utils.DBUtils;

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

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

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

import java.sql.Connection;

import java.sql.DatabaseMetaData;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.List;

import java.util.Map;

@RestController

public class DBController {

     @PostMapping ( "/connect" )

     public ResultModel connect( @RequestBody Db db) {

         Connection connection = DBUtils.init(db);

         if (connection == null ) {

             return ResultModel.fail( "数据库连接失败" );

         } else {

             return ResultModel.success( "数据库连接成功" );

         }

     }

     @PostMapping ( "/config" )

     public ResultModel config( @RequestBody Map<String,Object> map) {

         String packetName = (String)map.get( "packetName" );

         try {

             //获取数据库连接

             Connection connection = DBUtils.getConnection();

             //获取数据库元数据

             DatabaseMetaData metaData = connection.getMetaData();

             //获取数据库所有的表

             ResultSet rs = metaData.getTables(connection.getCatalog(), null , null , null );

             List<TableClass> list = new ArrayList<>();

             while (rs.next()) {

                 TableClass tableClass = new TableClass();

                 tableClass.setPacketName(packetName);

                 //获取表名

                 String tableName = rs.getString( "TABLE_NAME" );

                 //数据库表下划线的字段转成驼峰，且首字母大写

                 String modelName = CaseFormat.LOWER_UNDERSCORE.to(CaseFormat.UPPER_CAMEL, tableName);

                 tableClass.setTableName(tableName);

                 tableClass.setModelName(modelName);

                 tableClass.setServiceName(modelName + "Service" );

                 tableClass.setMapperName(modelName + "Mapper" );

                 tableClass.setControllerName(modelName + "Controller" );

                 list.add(tableClass);

             }

             return ResultModel.success( "数据库信息读取成功" ,list);

         } catch (SQLException e) {

             e.printStackTrace();

             return ResultModel.fail( "数据库信息读取失败" );

         }

     }

}

package com.yl.generate_code.controller;

import com.yl.generate_code.model.ResultModel;

import com.yl.generate_code.model.TableClass;

import com.yl.generate_code.service.GenerateCodeService;

import org.springframework.beans.factory.annotation.Autowired;

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

import javax.servlet.http.HttpServletRequest;

import java.util.List;

@RestController

public class GenerateCodeController {

     @Autowired

     private GenerateCodeService generateCodeService;

     @PostMapping ( "/generateCode" )

     public ResultModel generateCode( @RequestBody List<TableClass> list, HttpServletRequest request) {

         return generateCodeService.generateCode(list,request.getServletContext().getRealPath( "/" ));

     }

}

package com.yl.generate_code.model;

import java.io.Serializable;

public class ColumnClass implements Serializable {

     //实体类属性名

     private String propertyName;

     //实体类属性名对应的表的字段名

     private String columnName;

     //字段类型

     private String type;

     //备注

     private String remark;

     //该字段是否为主键

     private Boolean isPrimary;

     public String getPropertyName() {

         return propertyName;

     }

     public void setPropertyName(String propertyName) {

         this .propertyName = propertyName;

     }

     public String getColumnName() {

         return columnName;

     }

     public void setColumnName(String columnName) {

         this .columnName = columnName;

     }

     public String getType() {

         return type;

     }

     public void setType(String type) {

         this .type = type;

     }

     public String getRemark() {

         return remark;

     }

     public void setRemark(String remark) {

         this .remark = remark;

     }

     public Boolean getPrimary() {

         return isPrimary;

     }

     public void setPrimary(Boolean primary) {

         isPrimary = primary;

     }

     @Override

     public String toString() {

         return "ColumnClass{" +

                 "propertyName='" + propertyName + '\ '' +

                 ", columnName='" + columnName + '\ '' +

                 ", type='" + type + '\ '' +

                 ", remark='" + remark + '\ '' +

                 ", isPrimary=" + isPrimary +

                 '}' ;

     }

}

package com.yl.generate_code.model;

import java.io.Serializable;

public class Db implements Serializable {

     private String username;

     private String password;

     private String url;

     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;

     }

     public String getUrl() {

         return url;

     }

     public void setUrl(String url) {

         this .url = url;

     }

}

package com.yl.generate_code.model;

import java.io.Serializable;

public class ResultModel implements Serializable {

     private Integer code;

     private String msg;

     private Object obj;

     public static ResultModel success(String msg,Object obj) {

         return new ResultModel( 200 ,msg,obj);

     }

     public static ResultModel success(String msg) {

         return new ResultModel( 200 ,msg, null );

     }

     public static ResultModel fail(String msg,Object obj) {

         return new ResultModel( 500 ,msg,obj);

     }

     public static ResultModel fail(String msg) {

         return new ResultModel( 500 ,msg, null );

     }

     private ResultModel() {

     }

     public ResultModel(Integer code, String msg, Object obj) {

         this .code = code;

         this .msg = msg;

         this .obj = obj;

     }

     public Integer getCode() {

         return code;

     }

     public void setCode(Integer code) {

         this .code = code;

     }

     public String getMsg() {

         return msg;

     }

     public void setMsg(String msg) {

         this .msg = msg;

     }

     public Object getObj() {

         return obj;

     }

     public void setObj(Object obj) {

         this .obj = obj;

     }

}

package com.yl.generate_code.model;

import java.io.Serializable;

import java.util.ArrayList;

import java.util.Date;

import java.util.List;

public class TableClass implements Serializable {

     private String tableName;

     private String modelName;

     private String serviceName;

     private String mapperName;

     private String controllerName;

     private String packetName;

     private String createDate;

     private List<ColumnClass> columns = new ArrayList<>();

     public String getTableName() {

         return tableName;

     }

     public void setTableName(String tableName) {

         this .tableName = tableName;

     }

     public String getModelName() {

         return modelName;

     }

     public void setModelName(String modelName) {

         this .modelName = modelName;

     }

     public String getServiceName() {

         return serviceName;

     }

     public void setServiceName(String serviceName) {

         this .serviceName = serviceName;

     }

     public String getMapperName() {

         return mapperName;

     }

     public void setMapperName(String mapperName) {

         this .mapperName = mapperName;

     }

     public String getControllerName() {

         return controllerName;

     }

     public void setControllerName(String controllerName) {

         this .controllerName = controllerName;

     }

     public String getPacketName() {

         return packetName;

     }

     public void setPacketName(String packetName) {

         this .packetName = packetName;

     }

     public List<ColumnClass> getColumns() {

         return columns;

     }

     public void setColumns(List<ColumnClass> columns) {

         this .columns = columns;

     }

     public String getCreateDate() {

         return createDate;

     }

     public void setCreateDate(String createDate) {

         this .createDate = createDate;

     }

}

<!DOCTYPE html>

< html lang = "en" >

< head >

     < meta charset = "UTF-8" >

     < title >Title</ title >

     <!--引入vue.js,elementui和axios-->

     < script src = "https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js" ></ script >

     <!-- 引入样式 -->

     < link rel = "stylesheet" href = "https://unpkg测试数据/element-ui/lib/theme-chalk/index.css" >

     <!-- 引入组件库 -->

     < script src = "https://unpkg测试数据/element-ui/lib/index.js" ></ script >

     < script src = "https://unpkg测试数据/axios/dist/axios.min.js" ></ script >

</ head >

< body >

< div id = "app" >

     < table >

         < tr >

             < td >< el-tag size = "mini" >数据库用户名:</ el-tag ></ td >

             < td >< el-input size = "mini" v-model = "db.username" ></ el-input ></ td >

         </ tr >

         < tr >

             < td >< el-tag size = "mini" >数据库密码:</ el-tag ></ td >

             < td >< el-input size = "mini" v-model = "db.password" ></ el-input ></ td >

         </ tr >

         < tr >

             < td >< el-tag size = "mini" >数据库连接地址:</ el-tag ></ td >

             < td >< el-input size = "mini" v-model = "db.url" >

                 < template slot = "prepend" >jdbc:mysql://</ template >

                 < template slot = "append" >?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai</ template >

             </ el-input ></ td >

         </ tr >

     </ table >

     < div style = "display: flex" >

         < el-button type = "primary" size = "mini" @ click = "connect" :disabled = "!enableButton" >连接数据库</ el-button >

         < div style = "color: red;font-weight: bold" >{{msg}}</ div >

         < el-input v-model = "packetName" size = "mini" style = "width:300px" ></ el-input >

         < el-button size = "mini" type = "primary" @ click = "config" >配置</ el-button >

     </ div >

     < el-table

             :data = "tableData"

             stripe

             border

             style = "width: 100%" >

         < el-table-column

                 prop = "tableName"

                 label = "表名称"

                 width = "180" >

         </ el-table-column >

         < el-table-column

                 label = "实体类名称"

                 width = "180" >

             < template slot-scope = "scope" >

                 < el-input v-model = "scope.row.modelName" ></ el-input >

             </ template >

         </ el-table-column >

         < el-table-column

                 label = "mapper名称" >

             < template slot-scope = "scope" >

                 < el-input v-model = "scope.row.mapperName" ></ el-input >

             </ template >

         </ el-table-column >

         < el-table-column

                 label = "service名称" >

             < template slot-scope = "scope" >

                 < el-input v-model = "scope.row.serviceName" ></ el-input >

             </ template >

         </ el-table-column >

         < el-table-column

                 label = "controller名称" >

             < template slot-scope = "scope" >

                 < el-input v-model = "scope.row.controllerName" ></ el-input >

             </ template >

         </ el-table-column >

     </ el-table >

     < div >

         < el-button type = "success" size = "mini" @ click = "generateCode" >生成代码</ el-button >

         < div style = "color: green;font-weight: bold" >{{result}}</ div >

         < div >{{codePath}}</ div >

     </ div >

</ div >

< script >

     new Vue({

         el:"#app",

         data() {

             return{

                 result: '',

                 codePath: '',

                 tableData:[],

                 packetName: 'com.yl',

                 msg : "数据库未连接",

                 enableButton: true,

                 db: {

                     username: "root",

                     password: "root",

                     url : "localhost:3306/demo"

                 }

             }

         },

         methods: {

             connect() {

                 let _this = this

                 this.db.url = "jdbc:mysql://" + this.db.url + "?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai"

                 axios.post("/connect",this.db).then(res => {

                     console.log(res.data)

                     _this.db = {

                         username: "root",

                         password: "root",

                         url : "localhost:3306/demo"

                     }

                     _this.msg = res.data.msg

                     _this.enableButton = false

                 }).catch(err => {

                     console.log(err)

                 })

             },

             config() {

                 let _this = this

                 axios.post("/config",{packetName: _this.packetName}).then(res => {

                     console.log(res.data)

                     _this.msg = res.data.msg

                     _this.tableData = res.data.obj

                 }).catch(err => {

                     console.log(err)

                 })

             },

             generateCode() {

                 let _this = this

                 axios.post("/generateCode",_this.tableData).then(res => {

                     console.log(res.data)

                     _this.result = res.data.msg

                     _this.codePath = res.data.obj

                 }).catch(err => {

                     console.log(err)

                 })

             }

         }

     })

</ script >

</ body >

</ html >

package com.yl.generate_code.service;

import com.yl.generate_code.model.ResultModel;

import com.yl.generate_code.model.TableClass;

import javax.servlet.http.HttpServletRequest;

import java.util.List;

public interface GenerateCodeService {

     ResultModel generateCode(List<TableClass> list, String realpath);

}

package com.yl.generate_code.service.impl;

import com.google测试数据mon.base.CaseFormat;

import com.yl.generate_code.model.ColumnClass;

import com.yl.generate_code.model.ResultModel;

import com.yl.generate_code.model.TableClass;

import com.yl.generate_code.service.GenerateCodeService;

import com.yl.generate_code.utils.DBUtils;

import freemarker.cache.ClassTemplateLoader;

import freemarker.template.Configuration;

import freemarker.template.Template;

import freemarker.template.TemplateException;

import org.springframework.stereotype.Service;

import javax.servlet.http.HttpServletRequest;

import java.io.*;

import java.sql.Connection;

import java.sql.DatabaseMetaData;

import java.sql.ResultSet;

import java.text.SimpleDateFormat;

import java.util.ArrayList;

import java.util.Date;

import java.util.List;

@Service

public class GenerateCodeServiceImpl implements GenerateCodeService {

     Configuration cfg = null ;

     {

         cfg = new Configuration(Configuration.VERSION_2_3_31);

         cfg.setTemplateLoader( new ClassTemplateLoader(GenerateCodeServiceImpl. class , "/templates" ));

         cfg.setDefaultEncoding( "utf-8" );

     }

     @Override

     public ResultModel generateCode(List<TableClass> list, String realpath) {

         try {

             Template modelTemplate = cfg.getTemplate( "Model.java.ftl" );

             Template serviceTemplate = cfg.getTemplate( "Service.java.ftl" );

             Template serviceImplTemplate = cfg.getTemplate( "ServiceImpl.java.ftl" );

             Template mapperTemplate = cfg.getTemplate( "Mapper.java.ftl" );

             Template mapperXmlTemplate = cfg.getTemplate( "Mapper.xml.java.ftl" );

             Template controllerTemplate = cfg.getTemplate( "Controller.java.ftl" );

             Connection connection = DBUtils.getConnection();

             DatabaseMetaData metaData = connection.getMetaData();

             for (TableClass tableClass : list) {

                 //根据表名获取该表的所有字段

                 ResultSet columns = metaData.getColumns(connection.getCatalog(), null , tableClass.getTableName(), null );

                 //获取该表的所有主键

                 ResultSet primaryKeys = metaData.getPrimaryKeys(connection.getCatalog(), null , tableClass.getTableName());

                 List<ColumnClass> columnClasses = new ArrayList<>();

                 while (columns.next()) {

                     //获取字段名

                     String column_name = columns.getString( "COLUMN_NAME" );

                     //获取字段类型

                     String type_name = columns.getString( "TYPE_NAME" );

                     //获取字段注释

                     String remark = columns.getString( "REMARKS" );

                     ColumnClass columnClass = new ColumnClass();

                     columnClass.setColumnName(column_name);

                     columnClass.setType(type_name);

                     columnClass.setRemark(remark);

                     columnClass.setPropertyName(CaseFormat.LOWER_UNDERSCORE.to(CaseFormat.UPPER_CAMEL,column_name));

                     //指标挪到第一

                     primaryKeys.first();

                     while (primaryKeys.next()) {

                         String primaryKey = primaryKeys.getString( "COLUMN_NAME" );

                         if (column_name.equals(primaryKey)) {

                             columnClass.setPrimary( true );

                         }

                     }

                     columnClasses.add(columnClass);

                 }

                 tableClass.setColumns(columnClasses);

                 SimpleDateFormat sdf = new SimpleDateFormat( "yyyy-MM-dd" );

                 tableClass.setCreateDate(sdf.format( new Date()));

                 String path = realpath + "/" + tableClass.getPacketName().replace( "." , "/" );

                 generate(modelTemplate,tableClass,path+ "/model/" , 1 );

                 generate(serviceTemplate,tableClass,path+ "/service/" , 1 );

                 generate(serviceImplTemplate,tableClass,path+ "/service/impl" , 1 );

                 generate(mapperTemplate,tableClass,path+ "/mapper/" , 1 );

                 generate(mapperXmlTemplate,tableClass,path+ "/mapper/" , 2 );

                 generate(controllerTemplate,tableClass,path+ "/controller/" , 1 );

             }

             return ResultModel.success( "代码已生成" ,realpath);

         } catch (Exception e) {

             e.printStackTrace();

             return ResultModel.fail( "代码生成失败" );

         }

     }

     private void generate(Template template,TableClass tableClass,String path,Integer flag) throws IOException, TemplateException {

         File file = new File(path);

         if (!file.exists()) {

             file.mkdirs();

         }

         String fileName;

         if (flag == 1 ) {

             fileName = path + "/" + tableClass.getModelName() + template.getName().replace( ".ftl" , "" ).replace( "Model" , "" );

         } else {

             fileName = path + "/" + tableClass.getModelName() + template.getName().replace( ".ftl" , "" ).replace( ".java" , "" );

         }

         FileOutputStream fos = new FileOutputStream(fileName);

         OutputStreamWriter  out = new OutputStreamWriter(fos);

         template.process(tableClass,out);

         fos.close();

         out.close();

     }

}