The method addBatch(String) is undefined for the type String

[a_elegant_joker]

String.addBatch(sql1);报错
这是 DAOTest类

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DAOTest {
	Connection conn;
	Statement stmt;
	ResultSet rs;
	public Connection getConn() {
		return conn;
	}
	public Statement getStmt() {
		return stmt;
	}
	public ResultSet getRs() {
		return rs;
	}
	public DAOTest(Connection conn) {
	this.conn=conn;
	try {
		stmt=conn.createStatement();
	} catch (SQLException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}
	}
	public void createTable() throws SQLException {
		stmt.executeUpdate("drop table if exists 'jdbc_test'");
		String sql="create table jdbc_test(id int,name varchar(100))";
		stmt.executeUpdate(sql);
		System.out.println("jdbc_test表建立完成");
	}
	public void insert() throws SQLException{
		String sql1="insert into jdbc_test values(1,'tom')";
		String sql2="insert into jdbc_test values(2,'张三')";
		String sql3="insert into jdbc_test values(3,'999')";
		String.addBatch(sql1);
		String.addBatch(sql2);
		String.addBatch(sql3);
		
		int[] results=stmt.executeBatch();
		for(int i=0;i<results.length;i++) {
			System.out.println("第"+(i+1)+"次插入返回"+results[0]+"条结果");
		}
	}
		public void select() throws SQLException{
			String sql="select id,name from jdbc_test";
			rs=stmt.executeQuery(sql);
			System.out.println("id\tname");
			System.out.println("---------------------");
			while(rs.next()) {
				String id=rs.getString("id");
				String name=rs.getString("name");
				System.out.println(id+"\t"+name+"\n");
				
			}
		}
		public static void main(String[]args) {
			Connection conn=JDBCUtil.getConnection();
			DAOTest dao=new DAOTest(conn);
			try {
				dao.createTable();
				dao.insert();
				dao.select();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}finally {
				JDBCUtil.close(dao.getRs(), dao.getStmt(), dao.getConn());
			}
			
		}
	}

这是JDBCUtil 类

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class JDBCUtil {
	
	// 静态方法完成加载
	static {
		String driverName = "com.mysql.jdbc.Driver";
		try {
			Class.forName(driverName);
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	// 提供方法连接数据库
	public static Connection getConnection() {
		Connection conn = null;
		try {
			DriverManager.getConnection("Jdbc:mysql://127.0.0.1/useUnicode=true&CharacterEncoding=utf8", "root,",
					"666666");
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return conn;

	}
	//关闭连接
	public static void close(ResultSet rs,Statement stmt,Connection conn) {
		try {
			if(rs!=null)
				rs.close();
		} catch (Exception ex) {
			// TODO Auto-generated catch block
			ex.printStackTrace();
		}
		try {
			if(stmt!=null)
				stmt.close(); 
		} catch (Exception ex) {
			// TODO Auto-generated catch block
			ex.printStackTrace();
		}
		try {
			if(conn!=null)
				conn.close();
		} catch (Exception ex) {
			// TODO Auto-generated catch block
			ex.printStackTrace();
		}
	}
	
}

[李德胜1995]

stmt.addBatch(sql);

[a_elegant_joker]

谢谢大神了,,,,