dsProject/dsUtils/src/main/java/com/dsideal/Tools/GenerateCode.java

package com.dsideal.Tools;

import cn.hutool.core.date.DateUnit;
import cn.hutool.core.io.FileUtil;
import com.dsideal.Utils.dsKit;
import com.jfinal.kit.PropKit;
import com.jfinal.plugin.activerecord.ActiveRecordPlugin;
import com.jfinal.plugin.hikaricp.HikariCpPlugin;

import javax.sql.DataSource;
import java.io.File;
import java.sql.*;
import java.util.*;

public class GenerateCode {

    // JavaBean保存的位置
    public static String beanPath;
    // JavaBean包名
    public static String beanPackage;

    // mysql与java的数据类型映射
    public static Map<String, String> dataTypeMap = new HashMap<>();

    /**
     * 获取当前数据库下的表
     *
     * @return List<String>
     * @throws Exception
     */
    public static List<String> getTableNames(Connection conn) throws Exception {
        List<String> tables = new ArrayList<>();
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("show tables");
        while (rs.next()) {
            String tableName = rs.getString(1);
            if (tableName.equals(PropKit.get("tableName"))) {
                tables.add(tableName);
            }
        }
        rs.close();
        stmt.close();
        return tables;
    }


    /**
     * 获得某表的注释信息+列信息
     *
     * @param table
     * @return
     * @throws Exception
     */
    public static void getStructure(Connection conn, String table) throws Exception {
        StringBuilder sb = new StringBuilder();

        //表注释
        String comment = "";
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("show create table " + table);
        if (rs != null && rs.next()) {
            String createDDL = rs.getString(2);
            int index = createDDL.indexOf("COMMENT='");
            if (index >= 0) {
                comment = createDDL.substring(index + 9);
                comment = comment.substring(0, comment.length() - 1);
            }
        }
        //类名
        table = capitalizeFirstLetter(table);
        String className = toCamelCase(table);

        //包名
        sb.append("package " + beanPackage + ";\n");
        sb.append("\n");

        sb.append("import lombok.Setter;\n");
        sb.append("import lombok.Getter;\n");

        //表描述
        sb.append("// " + comment + "\n");
        sb.append("public class " + className + " {\n");

        List<String> fields = new ArrayList<>();
        //字段信息
        rs = stmt.executeQuery("show full columns from " + table);
        while (rs.next()) {
            String Type = rs.getString("Type");
            String Field = rs.getString("Field");
            fields.add(Field);

            if (Type.contains("(")) {
                Type = Type.substring(0, Type.indexOf("("));
            }
            Type = Type.toUpperCase();

//            System.out.println(rs.getString("Key"));//是不是主键 PRI是主键
            sb.append("    // " + rs.getString("Comment") + "\n");
            sb.append("    @Getter\n");
            sb.append("    @Setter\n");
            sb.append("    private " + dataTypeMap.get(Type) + " " + Field + ";\n");
        }
        sb.append("\n");
        sb.append("    public String toString(){\n");
        sb.append("        return \"{");

        for (int i = 0; i < fields.size(); i++) {
            String field = fields.get(i);
            sb.append(" " + field + ": \" + " + field + " +\"");
            if (i < fields.size() - 1) {
                sb.append(",");
            }
        }
        sb.append("}\";\n");
        sb.append("    }\n");
        sb.append("}\n");
        String fileName = beanPath + File.separator + className + ".java";
        FileUtil.writeUtf8String(sb.toString(), fileName);
        //关闭连接
        rs.close();
        stmt.close();
    }

    /**
     * 功能：初始化数据库类型映射
     */
    public static void initMap() {
        //mysql与java的数据类型映射
        dataTypeMap.put("INT", "int");
        dataTypeMap.put("BIGINT", "long");
        dataTypeMap.put("DOUBLE", "double");
        dataTypeMap.put("FLOAT", "float");
        dataTypeMap.put("TINYINT", "int");
        dataTypeMap.put("DATE", "java.util.Date");
        dataTypeMap.put("TIMESTAMP", "java.util.Date");
        dataTypeMap.put("BIGINT UNSIGNED", "long");
        dataTypeMap.put("INT UNSIGNED", "long");
        dataTypeMap.put("MEDIUMINT", "int");
        dataTypeMap.put("MEDIUMINT UNSIGNED", "long");
        dataTypeMap.put("SMALLINT", "int");
        dataTypeMap.put("SMALLINT UNSIGNED", "long");
        dataTypeMap.put("TINYINT UNSIGNED", "long");
        dataTypeMap.put("LONGTEXT", "String");
        dataTypeMap.put("VARCHAR", "String");
        dataTypeMap.put("CHAR", "String");
        dataTypeMap.put("TEXT", "String");
        dataTypeMap.put("DATETIME", "java.util.Date");
        dataTypeMap.put("DECIMAL", "BigDecimal");
        dataTypeMap.put("BOOLEAN", "boolean");
    }

    public static void main(String[] args) throws Exception {
        //加载配置文件
        PropKit.use("application.properties");
        beanPackage = PropKit.get("beanPackage");
        beanPath = PropKit.get("beanPath");
        beanPath = beanPath + "/" + beanPackage.replace(".", "/");
        if (!FileUtil.exist(beanPath)) {
            FileUtil.mkdir(beanPath);
        }
        initMap();

        // 配置Druid数据源插件
        HikariCpPlugin hpPlugin = new HikariCpPlugin(PropKit.get("jdbcUrl"), PropKit.get("user"),
                PropKit.get("password").trim(), PropKit.get("driverClassName"));
        hpPlugin.start();

        // 配置ActiveRecord插件
        ActiveRecordPlugin arp = new ActiveRecordPlugin(hpPlugin);
        hpPlugin.start();
        arp.start();
        DataSource dataSource = hpPlugin.getDataSource();
        // 数据库连接
        Connection conn = dataSource.getConnection();

        //开始生成
        List<String> tables = getTableNames(conn);

        String tableNames = "";
        //表描述
        for (String table : tables) {
            getStructure(conn, table);
            tableNames += table + ",";
        }
        //去掉最后的逗号
        tableNames = tableNames.substring(0, tableNames.length() - 1);

        //关闭数据库
        conn.close();
        arp.stop();
        hpPlugin.stop();

        System.out.println(dsKit.getCurrentTimeStr() + "      恭喜，表" + tableNames + "代码已成功生成！");
    }


    /**
     * 将表名转换为驼峰命名法
     */
    private static String toCamelCase(String tableName) {
        StringBuilder sb = new StringBuilder();
        boolean upperCase = false;

        for (char c : tableName.toCharArray()) {
            if (c == '_') {
                upperCase = true;
            } else if (upperCase) {
                sb.append(Character.toUpperCase(c));
                upperCase = false;
            } else {
                sb.append(c);
            }
        }
        return sb.toString();
    }

    /**
     * 功能：首字母转大写
     *
     * @param input
     * @return
     */
    public static String capitalizeFirstLetter(String input) {
        // 检查输入是否为空或者null
        if (input == null || input.isEmpty()) {
            return input;
        }

        // 将第一个字符转换为大写，然后与其余部分拼接
        return input.substring(0, 1).toUpperCase() + input.substring(1);
    }
}