JDBC静态sql语句连接的工具类编写

为了方便静态SQL语句进行增删改查的操作，编写了一个工具类进行操作。

import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map;

public class JdbcUtil {  // 定义数据库驱动  private static final String DRIVER_NAME = "oracle.jdbc.driver.OracleDriver";

 // 获取URL  private static final String URL = "jdbc:oracle:thin:@172.22.246.26:1521:orcl";

 // 获取用户名  private static final String USER = "java1";

 // 获取密码  private static final String PASSWORD = "java1";

 static {   try {    // 初始化JDBC驱动，并让驱动加载到JVM中    Class.forName(DRIVER_NAME);   } catch (ClassNotFoundException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }  }

 /*   * 获取数据库连接对象   */  public static Connection getConnection() {   Connection conn = null;   try {    // 获取数据库连接    conn = DriverManager.getConnection(URL, USER, PASSWORD);   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }   return conn;  }

 /*   * 更新数据库   */  public void update(String sql) {   Connection conn = getConnection();   Statement stmt = null;   if (conn != null) {    try {     stmt = conn.createStatement();     stmt.executeUpdate(sql);    } catch (SQLException e) {     // TODO Auto-generated catch block     e.printStackTrace();    }   }   close(stmt);   close(conn);  }

 /*   * 数据查询   */  public List<Map<String, Object>> query(String sql) {   List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();   Connection conn = getConnection();   Statement stmt = null;   ResultSet rs = null;   if (conn != null) {    try {     stmt = conn.createStatement();     rs = stmt.executeQuery(sql);     // 获取结果集的列数， 为下面的for循环做准备     int count = rs.getMetaData().getColumnCount();

    while (rs.next()) {      // 创建map，将我们每一行的值以键值对的形式（列-值）存储      Map<String, Object> map = new HashMap<String, Object>();

     for (int i = 1; i <= count; i++) {       // 循环获取列名       String columnName = rs.getMetaData().getColumnName(i);       // 获取值，由于值的多样性，我们无法确定它是什么类型。       Object value = rs.getObject(i);       map.put(columnName, value);      }      list.add(map);     }    } catch (SQLException e) {     // TODO Auto-generated catch block     e.printStackTrace();    }   }   close(rs);   close(stmt);   close(conn);   return list;  }

 /*   * 关闭对象   */  public static void close(Object o) {   if (o == null) {    return;   }

  if (o instanceof ResultSet) {    try {     ((ResultSet) o).close();    } catch (SQLException e) {     e.printStackTrace();    }   } else if (o instanceof Statement) {    try {     ((Statement) o).close();    } catch (SQLException e) {     e.printStackTrace();    }   } else if (o instanceof Connection) {    try {     ((Connection) o).close();    } catch (SQLException e) {     e.printStackTrace();    }   }  } }