Java 一键生成表controller、service、mapper等文件（不引入插件）

我们在开发过程中，如果数据库已经存在表了，那么我们可以直接用下面工具类，一键生成对应的 entity、service、serviceImpl、mapper、mapper.xml 五个相关文件，只需要配置好数据库访问的相关信息，执行 main 方法即可，不用引入 myabtis 的一键生成依赖。 

package com.zdb;import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.text.SimpleDateFormat;
import java.util.*;/*** @author Yuanqiang.Zhang* @since 2023/5/15*/
public class GeneratorTool {/** 数据源配置 */private static final String IP = "localhost";private static final int PORT = 3306;private static final String DATABASE = "zyq";private static final String USERNAME = "root";private static final String PASSWORD = "12345";/** 基础配置 */private static final String AUTHOR = "zyq";private static final String BASE_PACKAGE = "com.zdb";private static final String[] TABLE_NAMES = {"t_bom_price", };private static final String[] IGNORE_PREFIXES = {"z_"};/** 指定生成路径（如果配置了该路径，则所有文件将统一生成到该路径下，如果不配置，则将按照标准生成到项目中） */private static final String PATH = "D:\\code2023\\temp";public static void main(String[] args) throws Exception {Connection conn = getConnection();for (String tableName : TABLE_NAMES) {createTableFiles(conn, tableName);}}private static String getWithoutPrefixTableName(String tableName) {for (String s : IGNORE_PREFIXES) {if (tableName.startsWith(s)) {return tableName.substring(s.length());}}return tableName;}public static void createTableFiles(Connection conn, String tableName) {List fields = getTableFields(conn, tableName);String withoutPrefixTableName = getWithoutPrefixTableName(tableName);String className = getClassName(withoutPrefixTableName);createEntity(fields, tableName, className, withoutPrefixTableName);createMapper(withoutPrefixTableName, className);createMapperXml(withoutPrefixTableName, className);createService(withoutPrefixTableName, className);createServiceImpl(withoutPrefixTableName, className);createController(withoutPrefixTableName, className);}public static void createController(String tableName, String className) {StringBuilder sb = new StringBuilder();sb.append(String.format("package %s.controller;\n\n", BASE_PACKAGE));sb.append(String.format("import %s.service.%sService;\n", BASE_PACKAGE, className));sb.append("import lombok.extern.slf4j.Slf4j;\n");sb.append("import org.springframework.web.bind.annotation.RequestMapping;\n");sb.append("import org.springframework.web.bind.annotation.RestController;\n");sb.append("import org.springframework.beans.factory.annotation.Autowired;\n\n");sb.append("/**\n");sb.append(String.format(" * @author %s\n", AUTHOR));sb.append(String.format(" * @since %s\n", formatDateTime(new Date())));sb.append(" */\n");sb.append("@RestController\n");sb.append("@Slf4j\n");String path = String.valueOf(className.toCharArray()[0]).toLowerCase() + className.substring(1);sb.append(String.format("@RequestMapping(\"/%s\")\n", path));sb.append(String.format("public class %sController {\n\n", className));sb.append("    @Autowired\n");sb.append(String.format("    private %sService service;\n\n", className));sb.append("}\n");String fileName = className + "Controller.java";String filePath;if (Objects.nonNull(PATH) && !PATH.trim().isEmpty()) {filePath = PATH+ "\\" + fileName;} else {filePath = getBasePath() + "/controller/" + fileName;}File file = new File(filePath);if (file.exists()) {System.out.println(tableName + " 的 Controller 类已经存在，不再生成。");} else {writeFileContent(file, sb.toString());System.out.println(tableName + " 的 Controller 类生成完毕。");}}public static void createServiceImpl(String tableName, String className) {StringBuilder sb = new StringBuilder();sb.append(String.format("package %s.service.impl;\n\n", BASE_PACKAGE));sb.append("import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;\n");sb.append(String.format("import %s.entity.%s;\n", BASE_PACKAGE, className));sb.append(String.format("import %s.mapper.%sMapper;\n", BASE_PACKAGE, className));sb.append(String.format("import %s.service.%sService;\n", BASE_PACKAGE, className));sb.append("import lombok.extern.slf4j.Slf4j;\n");sb.append("import org.springframework.beans.factory.annotation.Autowired;\n");sb.append("import org.springframework.stereotype.Service;\n\n");sb.append("/**\n");sb.append(String.format(" * @author %s\n", AUTHOR));sb.append(String.format(" * @since %s\n", formatDateTime(new Date())));sb.append(" */\n");sb.append("@Slf4j\n");sb.append("@Service\n");sb.append(String.format("public class %sServiceImpl extends ServiceImpl<%sMapper, %s> implements %sService { \n\n", className, className, className, className));sb.append("    @Autowired\n");sb.append(String.format("    private %sMapper mapper;\n\n", className));sb.append("}\n");String fileName = className + "ServiceImpl.java";String filePath;if (Objects.nonNull(PATH) && !PATH.trim().isEmpty()) {filePath = PATH+ "\\" + fileName;} else {filePath = getBasePath() + "/service/impl/" + fileName;}File file = new File(filePath);if (file.exists()) {System.out.println(tableName + " 的 ServiceImpl 已经存在，不再生成。");} else {writeFileContent(file, sb.toString());System.out.println(tableName + " 的 ServiceImpl 生成完毕。");}}public static void createService(String tableName, String className) {StringBuilder sb = new StringBuilder();sb.append(String.format("package %s.service;\n\n", BASE_PACKAGE));sb.append("import com.baomidou.mybatisplus.extension.service.IService;\n");sb.append(String.format("import %s.entity.%s;\n\n", BASE_PACKAGE, className));sb.append("/**\n");sb.append(String.format(" * @author %s\n", AUTHOR));sb.append(String.format(" * @since %s\n", formatDateTime(new Date())));sb.append(" */\n");sb.append(String.format("public interface %sService extends IService<%s> {\n\n", className, className));sb.append("}\n");String fileName = className + "Service.java";String filePath;if (Objects.nonNull(PATH) && !PATH.trim().isEmpty()) {filePath = PATH+ "\\" + fileName;} else {filePath = getBasePath() + "/service/" + fileName;}File file = new File(filePath);if (file.exists()) {System.out.println(tableName + " 的 Service 类已经存在，不再生成。");} else {writeFileContent(file, sb.toString());System.out.println(tableName + " 的 Service 类生成完毕。");}}public static void createMapperXml(String tableName, String className) {StringBuilder sb = new StringBuilder();sb.append("\n");sb.append("\n");sb.append(String.format("\n\n", BASE_PACKAGE, className));sb.append("\n");String fileName = className + "Mapper.xml";String filePath = "src/main/resources/mapper/" + fileName;File file = new File(filePath);if (file.exists()) {System.out.println(tableName + " 的 Mapper.xml 已经存在，不再生成。");} else {writeFileContent(file, sb.toString());System.out.println(tableName + " 的 Mapper.xml 生成完毕。");}}public static void createMapper(String tableName, String className) {StringBuilder sb = new StringBuilder();sb.append(String.format("package %s.mapper;\n\n", BASE_PACKAGE));sb.append(String.format("import %s.entity.%s;\n", BASE_PACKAGE, className));sb.append("import com.baomidou.mybatisplus.core.mapper.BaseMapper;\n\n");sb.append("/**\n");sb.append(String.format(" * @author %s\n", AUTHOR));sb.append(String.format(" * @since %s\n", formatDateTime(new Date())));sb.append(" */\n");sb.append(String.format("public interface %sMapper extends BaseMapper<%s> {\n\n", className, className));sb.append("}\n");String fileName = className + "Mapper.java";String filePath;if (Objects.nonNull(PATH) && !PATH.trim().isEmpty()) {filePath = PATH+ "\\" + fileName;} else {filePath = getBasePath()  + "/mapper/" + fileName;}File file = new File(filePath);if (file.exists()) {System.out.println(tableName + " 的 Mapper 类已经存在，不再生成。");} else {writeFileContent(file, sb.toString());System.out.println(tableName + " 的 Mapper 类生成完毕。");}}public static void createEntity(List fields, String tableName, String className, String withoutPrefixTableName) {StringBuilder sb = new StringBuilder();sb.append(String.format("package %s.entity;\n\n", BASE_PACKAGE));sb.append("import com.baomidou.mybatisplus.annotation.*;\n");sb.append("import lombok.Data;\n\n");// 判断是否有 timestamp 类型if (hasDate(fields)) {sb.append("import java.util.Date;\n\n");}sb.append("/**\n");sb.append(" * @author " + AUTHOR + "\n");sb.append(" * @since ").append(formatDateTime(new Date())).append("\n");sb.append(" */\n");sb.append("@Data\n");sb.append(String.format("@TableName(\"%s\")\n", tableName));sb.append(String.format("public class %s {\n\n", className));for (String[] attrs : fields) {String columnName = attrs[0];String dataType = attrs[1];String columnComment = attrs[2];String columnKey = attrs[3];if ("PRI".equals(columnKey)) {sb.append("    /** 主键 */\n");sb.append(String.format("    @TableId(value = \"%s\", type = IdType.AUTO)\n", columnName));} else {if (Objects.nonNull(columnComment) && !columnComment.isEmpty()) {sb.append(String.format("    /** %s */\n", columnComment));}sb.append(String.format("    @TableField(value = \"%s\")\n", columnName));}String fieldName = getFieldName(columnName);if (dataType.endsWith("int")) {if ("bigint".equals(dataType)) {sb.append(String.format("    private Long %s;\n", fieldName));} else {sb.append(String.format("    private Integer %s;\n", fieldName));}} else if (dataType.endsWith("char") || dataType.endsWith("text")) {sb.append(String.format("    private String %s;\n", fieldName));} else if ("timestamp".equals(dataType) || "datetime".equals(dataType) || "date".equals(dataType)) {sb.append(String.format("    private Date %s;\n", fieldName));} else if ("double".equals(dataType)) {sb.append(String.format("    private Double %s;\n", fieldName));}  else if ("decimal".equals(dataType)) {sb.append(String.format("    private BigDecimal %s;\n", fieldName));} else {System.err.println("发现没有判断到的数据类型：" + dataType);}sb.append("\n");}sb.append("\n}");String fileName = className + ".java";String filePath;if (Objects.nonNull(PATH) && !PATH.trim().isEmpty()) {filePath = PATH+ "\\" + fileName;} else {filePath = getBasePath() + "/entity/" + fileName;}File file = new File(filePath);if (file.exists()) {System.out.println(withoutPrefixTableName + " 的 Entity 类已经存在，不再生成。");} else {writeFileContent(file, sb.toString());System.out.println(withoutPrefixTableName + " 的 Entity 类生成完毕。");}}private static String getBasePath() {return "src/main/java/" + BASE_PACKAGE.replace(".", "/");}private static String getFieldName(String columnName) {if (!columnName.contains("_")) {StringBuilder sb = new StringBuilder();char[] chars = columnName.toCharArray();sb.append(String.valueOf(chars[0]).toLowerCase());if (chars.length <= 1) {return sb.toString();} else {for (int i = 1; i < chars.length; i++) {sb.append(chars[i]);}}return sb.toString();}String s = getClassName(columnName);return String.valueOf(s.toCharArray()[0]).toLowerCase() + s.substring(1);}private static boolean hasDate(List fields) {if (Objects.isNull(fields) || fields.isEmpty()) {return false;}for (String[] attrs : fields) {String dataType = attrs[1];if ("timestamp".equals(dataType) || "datetime".equals(dataType)) {return true;}}return false;}private static List getTableFields(Connection conn, String tableName) {String sql = "SELECT * FROM information_schema.columns WHERE table_schema = '" + DATABASE + "' AND table_name = '" + tableName + "'";List fields = new ArrayList<>();try {Statement stat = conn.createStatement();ResultSet rs = stat.executeQuery(sql);while (rs.next()) {String columnName = rs.getString("COLUMN_NAME");String dataType = rs.getString("DATA_TYPE");String columnComment = rs.getString("COLUMN_COMMENT");String columnKey = rs.getString("COLUMN_KEY");String[] attrs = new String[4];attrs[0] = columnName;attrs[1] = dataType;attrs[2] = columnComment;attrs[3] = columnKey;fields.add(attrs);}} catch (Exception e) {e.printStackTrace();}return fields;}/*** 获取类名** @param tableName 表名* @return 类名*/private static String getClassName(String tableName) {char[] chars = tableName.toCharArray();boolean flag = true;StringBuilder sb = new StringBuilder();for (char c : chars) {if (c == '_') {flag = true;continue;}if (flag) {sb.append(String.valueOf(c).toUpperCase());} else {sb.append(String.valueOf(c).toLowerCase());}flag = false;}return sb.toString();}/*** 获取数据库链接** @return Connection*/private static Connection getConnection() throws Exception{Class.forName("com.mysql.cj.jdbc.Driver");String url = String.format("jdbc:mysql://%s:%s/%s", IP, PORT, DATABASE);return DriverManager.getConnection(url, USERNAME, PASSWORD);}/*** 将内容写入到文件中** @param file    文件* @param content 内容*/public static void writeFileContent(File file, String content) {String parentPath = file.getParent();if (Objects.nonNull(parentPath) && !parentPath.isEmpty()) {File parent = new File(parentPath);if (!parent.exists()) {parent.mkdirs();System.out.println("创建路径" + parent.getPath());}}if (!file.exists()) {try {System.out.println("创建文件：" + file.getPath());file.createNewFile();} catch (IOException e) {e.printStackTrace();}}try (FileWriter writer = new FileWriter(file)) {writer.write(content);writer.flush();} catch (IOException e) {e.printStackTrace();}}private static String formatDateTime(Date date) {return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.CHINA).format(date);}
}

本文来自互联网用户投稿，文章观点仅代表作者本人，不代表本站立场，不承担相关法律责任。如若转载，请注明出处。 如若内容造成侵权/违法违规/事实不符，请点击【内容举报】进行投诉反馈！