public class DbToPojo{//数据库连接信息private String url = "jdbc:mysql://localhost:3306/jdbc";private String user = "root";private String password = "root";//指定文件生成路径private String packageOutPath = "com.jpli.entity";private String drictory = new File("").getAbsolutePath() + "/src/" + packageOutPath.replace(".", "/");@Testpublic void test() throws Exception {File file = new File(drictory);if (!file.exists()) {file.mkdirs();}Connection connection = DriverManager.getConnection(url, user, password);List<String> tableClassNames = getTableClassName(connection);for (String tbName : tableClassNames) {String sql = "select * from " + tbName + " limit 1 ";PreparedStatement pStemt = connection.prepareStatement(sql);ResultSetMetaData rsmd = pStemt.getMetaData();int size = rsmd.getColumnCount();   //统计列String[] colnames = new String[size];String[] colTypes = new String[size];boolean f_util = false;boolean f_sql = false;for (int i = 0; i < size; i++) {//列名colnames[i] = rsmd.getColumnName(i + 1);//列类型colTypes[i] = rsmd.getColumnTypeName(i + 1);if (colTypes[i].equalsIgnoreCase("datetime") || colTypes[i].equalsIgnoreCase("time") || colTypes[i].equalsIgnoreCase("date") || colTypes[i].equalsIgnoreCase("timestamp")) {f_util = true;}if (colTypes[i].equalsIgnoreCase("image") || colTypes[i].equalsIgnoreCase("text")) {f_sql = true;}}//.java文件具体信息String content = parse(colnames, colTypes, tbName, f_util, f_sql);//当前工程的绝对路径/src/包名...类名.javaString outputPath = drictory + "/" + initcap(tbName) + ".java";//写入文件FileWriter fw = new FileWriter(outputPath);PrintWriter pw = new PrintWriter(fw);pw.println(content);pw.flush();pw.close();}}private String parse(String[] colnames, String[] colTypes, String tablename, boolean f_util, boolean f_sql) {StringBuffer sb = new StringBuffer();sb.append("package " + packageOutPath + ";\r\n");//判断是否导入工具包sb.append("import java.io.Serializable;\r\n");if (f_util) {sb.append("import java.util.Date;\r\n");}if (f_sql) {sb.append("import java.sql.*;\r\n");}sb.append("\r\n");//实体部分sb.append("\r\n\r\npublic class " + initcap(tablename) + " implements Serializable {\r\n");processAllAttrs(sb, colnames, colTypes);//属性processAllMethod(sb, colnames, colTypes, tablename);// 构造方法 get set方法sb.append("}\r\n");return sb.toString();}//获取所有表名public List<String> getTableClassName(Connection con) {List<String> tbs = new ArrayList<>();try {ResultSet rs = con.createStatement().executeQuery("show tables");while (rs.next()) {tbs.add(rs.getString(1));}} catch (SQLException e) {e.printStackTrace();}return tbs;}//字符串首字母改大写private String initcap(String str) {char[] ch = str.toCharArray();if (ch[0] >= 'a' && ch[0] <= 'z') {ch[0] = (char) (ch[0] - 32);}return new String(ch);}//生成所有属性private void processAllAttrs(StringBuffer sb, String[] colnames, String[] colTypes) {for (int i = 0; i < colnames.length; i++) {sb.append("\tprivate " + sqlType2JavaType(colTypes[i]) + " " + colnames[i] + ";\r\n");}}//数据库数据类型转java数据类型private String sqlType2JavaType(String sqlType) {if (sqlType.equalsIgnoreCase("bit")) {return "boolean";} else if (sqlType.equalsIgnoreCase("tinyint")) {return "byte";} else if (sqlType.equalsIgnoreCase("smallint")) {return "short";} else if (sqlType.equalsIgnoreCase("int")) {return "int";} else if (sqlType.equalsIgnoreCase("bigint")) {return "long";} else if (sqlType.equalsIgnoreCase("float")) {return "float";} else if (sqlType.equalsIgnoreCase("decimal") || sqlType.equalsIgnoreCase("numeric")|| sqlType.equalsIgnoreCase("real") || sqlType.equalsIgnoreCase("money")|| sqlType.equalsIgnoreCase("smallmoney")) {return "double";} else if (sqlType.equalsIgnoreCase("varchar") || sqlType.equalsIgnoreCase("char")|| sqlType.equalsIgnoreCase("nvarchar") || sqlType.equalsIgnoreCase("nchar")|| sqlType.equalsIgnoreCase("text")) {return "String";} else if (sqlType.equalsIgnoreCase("datetime") || sqlType.equalsIgnoreCase("date")|| sqlType.equalsIgnoreCase("timestamp") || sqlType.equalsIgnoreCase("time")) {return "Date";} else if (sqlType.equalsIgnoreCase("image")) {return "Blod";}return null;}//生成所有方法private void processAllMethod(StringBuffer sb, String[] colnames, String[] colTypes, String className) {//构造方法sb.append("\tpublic " + initcap(className) + "(){}\r\n");sb.append("\tpublic " + initcap(className) + "(");for (int i = 0; i < colnames.length; i++) {sb.append(sqlType2JavaType(colTypes[i]) + "\t" + colnames[i] + ",");}if (sb.substring(sb.length() - 1).equals(",")) {sb.deleteCharAt(sb.length() - 1);}sb.append("){");for (int i = 0; i < colnames.length; i++) {sb.append("\tthis." + colnames[i] + "=" + colnames[i] + ";\r\n");}sb.append("\t}\t\r\n");//get set 方法for (int i = 0; i < colnames.length; i++) {sb.append("\tpublic void set" + initcap(colnames[i]) + "(" + sqlType2JavaType(colTypes[i]) + " " +colnames[i] + "){\r\n");sb.append("\tthis." + colnames[i] + "=" + colnames[i] + ";\r\n");sb.append("\t}\r\n");sb.append("\tpublic " + sqlType2JavaType(colTypes[i]) + " get" + initcap(colnames[i]) + "(){\r\n");sb.append("\t\treturn " + colnames[i] + ";\r\n");sb.append("\t}\r\n");}//toStringsb.append("\t@Override\n" +"\tpublic String toString() {\n" +"\t\treturn \""+initcap(className)+"{\" ");sb.append("+\""+colnames[0]+"=\"+"+colnames[0]);for (int i = 1; i < colnames.length; i++) {sb.append("+\", "+colnames[i]+"=\"+"+colnames[i]+"");}sb.append("+'}';}");}
}