本例以JDBC 和 MY SQL DataBase为基础，演示执行SQL来查询数据，使用Statement和Prepared Statement两种方式。

一，示例代码

连接数据库uilt: MySqlJDBSUtil.java 
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package com.devnp.jdbc;

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

public class MySqlJDBSUtil {
	private static String driver = "com.mysql.jdbc.Driver";
	private static String url = "jdbc:mysql://127.0.0.1:3306/test?characterEncoding=utf8";
	private static String userName = "root"; // base on your login user name
	private static String password = "!qaz2wsx"; // base on your login user

	public static Connection getConnection() {
		
		Connection connection = null;
		try {
			Class.forName(driver);
			connection = DriverManager.getConnection(url, userName, password);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return connection;
	}

	public static void connectionClose(Connection connection) {
		if (connection != null) {
			try {
				connection.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
}

查询代码：
JDBCSelectRecord.java

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package com.devnp.jdbc;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Date;

public class JDBCSelectRecord {

	public static void main(String[] args) throws SQLException {
		// TODO Auto-generated method stub
		selectDbTableWithStatement();
		selectDbTableWithPreparedStatement();
	}
	
	/**
	 * 采用Statement 方式插入数据
	 * @throws SQLException
	 */
	public static void selectDbTableWithStatement() throws SQLException {
		Connection dbConnection = null;
		Statement statement = null;

		String selectTableSQL = "SELECT USER_ID, USERNAME, CREATED_BY, CREATED_DATE from USER_INFO";

		try {
			dbConnection = MySqlJDBSUtil.getConnection();
			statement = dbConnection.createStatement();

			System.out.println(selectTableSQL);

			// execute select SQL stetement
			ResultSet rs = statement.executeQuery(selectTableSQL);

			while (rs.next()) {

				String userid = rs.getString("USER_ID");
				String username = rs.getString("USERNAME");
				String createBy = rs.getString("CREATED_BY");
				Date createDate = rs.getDate("CREATED_DATE");

				System.out.println("userid : " + userid);
				System.out.println("username : " + username);
				System.out.println("Create By : " + createBy);
				System.out.println("Create Date : " + createDate);

			}

		} catch (SQLException e) {

			e.printStackTrace();

		} finally {

			if (statement != null) {
				statement.close();
			}

			if (dbConnection != null) {
				dbConnection.close();
			}

		}
	}
	
	/**
	 * 采用Prepared Statement 方式插入数据
	 * @throws SQLException
	 */
	public static void selectDbTableWithPreparedStatement() throws SQLException {
		Connection dbConnection = null;
		PreparedStatement preparedStatement = null;

		String selectSQL = "SELECT USER_ID, USERNAME, CREATED_BY, CREATED_DATE from USER_INFO WHERE USER_ID = ?";

		try {
			dbConnection = MySqlJDBSUtil.getConnection();
			preparedStatement = dbConnection.prepareStatement(selectSQL);
			preparedStatement.setInt(1, 1);

			// execute select SQL stetement
			ResultSet rs = preparedStatement.executeQuery();

			while (rs.next()) {

				String userid = rs.getString("USER_ID");
				String username = rs.getString("USERNAME");
				String createBy = rs.getString("CREATED_BY");
				Date createDate = rs.getDate("CREATED_DATE");

				System.out.println("userid : " + userid);
				System.out.println("username : " + username);
				System.out.println("Create By : " + createBy);
				System.out.println("Create Date : " + createDate);

			}

		} catch (SQLException e) {

			e.printStackTrace();

		} finally {

			if (preparedStatement != null) {
				preparedStatement.close();
			}

			if (dbConnection != null) {
				dbConnection.close();
			}

		}
	}

}

二，测试

运行结果： 
 SELECT USER_ID, USERNAME, CREATED_BY, CREATED_DATE from USER_INFO
 userid : 1
 username : devnp.com
 Create By : system
 Create Date : 2017-03-29
 userid : 2
 username : devnp.com
 Create By : system
 Create Date : 2017-03-29
 userid : 1
 username : devnp.com
 Create By : system
 Create Date : 2017-03-29
数据库截图：