JDBC通用方法实现

import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import java.util.UUID;

import javax.naming.Context;
import javax.naming.InitialContext;

public class TestDatasource {

final static String INITIAL_CONTEXT_FACTORY = "weblogic.jndi.WLInitialContextFactory";
final static String PROVIDER_URL = "t3://10.111.131.53:7001";
final static String JNDI = "my_jdbc";
/**
* 数据库驱动类名称
*/
private static final String DRIVER = "com.microsoft.sqlserver.jdbc.SQLServerDriver";

/**
* 连接字符串
*/
private static final String URLSTR = "jdbc:sqlserver://localhost:1433; databaseName=test";

/**
* 用户名
*/
private static final String USERNAME = "admin";

/**
* 密码
*/
private static final String USERPASSWORD = "111111";
/**
* 创建CallableStatement对象
*/
private CallableStatement callableStatement = null;
/**
* 创建数据库连接对象
*/
private Connection connnection = null;

/**
* 创建PreparedStatement对象
*/
private PreparedStatement preparedStatement = null;
/**
* 创建结果集对象
*/
private ResultSet resultSet = null;

static Context _ctx = null;

static {
//通过jndi
Hashtable<String, String> ht = new Hashtable<String, String>();
ht.put(Context.INITIAL_CONTEXT_FACTORY, INITIAL_CONTEXT_FACTORY);
ht.put(Context.PROVIDER_URL, PROVIDER_URL);
try {
_ctx = new InitialContext(ht);
} catch (Exception e) {
e.printStackTrace();
}

//通过加载驱动
try {
// 加载数据库驱动程序
Class.forName(DRIVER);
} catch (ClassNotFoundException e) {
System.out.println("加载驱动错误");
System.out.println(e.getMessage());
}
}

/**
* 建立数据库连接
* @return 数据库连接
*/
public Connection getConnectionForLoad() {
try {
// 获取连接
connnection = DriverManager.getConnection(URLSTR, USERNAME,
USERPASSWORD);
} catch (SQLException e) {
System.out.println(e.getMessage());
}
return connnection;
}
/**
*
* @return
*/
public Connection getConnection() {
Context ctx = null;
Connection con = null;
try {

ctx = _ctx;
javax.sql.DataSource ds = (javax.sql.DataSource) ctx.lookup(JNDI);
con = ds.getConnection();
} catch (Exception e) {

}
return con;
}

/**
* insert update delete SQL语句的执行的统一方法
* @param sql SQL语句
* @param params 参数数组，若没有参数则为null
* @return 受影响的行数
*/
public int executeUpdate(String sql, Object[] params) {
// 受影响的行数
int affectedLine = 0;
try {
// 获得连接
connnection = this.getConnection();
// 调用SQL
preparedStatement = connnection.prepareStatement(sql);

// 参数赋值
if (params != null) {
for (int i = 0; i < params.length; i++) {
preparedStatement.setObject(i + 1, params[i]);
}
}
// 执行
affectedLine = preparedStatement.executeUpdate();
} catch (SQLException e) {
System.out.println(e.getMessage());
} finally {
// 释放资源
closeAll();
}
return affectedLine;
}

/**
* 关闭所有资源
*/
private void closeAll() {
// 关闭结果集对象
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
System.out.println(e.getMessage());
}
}

// 关闭PreparedStatement对象
if (preparedStatement != null) {
try {
preparedStatement.close();
} catch (SQLException e) {
System.out.println(e.getMessage());
}
}
// 关闭Connection 对象
if (connnection != null) {
try {
connnection.close();
} catch (SQLException e) {
System.out.println(e.getMessage());
}
}
}

/**
* SQL 查询将查询结果直接放入ResultSet中
* @param sql SQL语句
* @param params 参数数组，若没有参数则为null
* @return 结果集
*/
private ResultSet executeQueryRS(String sql, Object[] params) {
try {
// 获得连接
connnection = this.getConnection();
// 调用SQL
preparedStatement = connnection.prepareStatement(sql);
// 参数赋值
if (params != null) {
for (int i = 0; i < params.length; i++) {
preparedStatement.setObject(i + 1, params[i]);
}
}
// 执行
resultSet = preparedStatement.executeQuery();

} catch (SQLException e) {
System.out.println(e.getMessage());
}
return resultSet;
}

/**
* 获取结果集，并将结果放在List中
*
* @param sql
* SQL语句
* @return List
*  结果集
*/
public List<Object> excuteQuery(String sql, Object[] params) {
// 执行SQL获得结果集
ResultSet rs = executeQueryRS(sql, params);
// 创建ResultSetMetaData对象
ResultSetMetaData rsmd = null;
// 结果集列数
int columnCount = 0;
try {
rsmd = rs.getMetaData();
// 获得结果集列数
columnCount = rsmd.getColumnCount();
} catch (SQLException e1) {
System.out.println(e1.getMessage());
}
// 创建List
List<Object> list = new ArrayList<Object>();
try {
// 将ResultSet的结果保存到List中
while (rs.next()) {
Map<String, Object> map = new HashMap<String, Object>();
for (int i = 1; i <= columnCount; i++) {
map.put(rsmd.getColumnLabel(i), rs.getObject(i));
}
list.add(map);
}
} catch (SQLException e) {
System.out.println(e.getMessage());
} finally {
// 关闭所有资源
closeAll();
}

return list;
}

/**
* 存储过程带有一个输出参数的方法
* @param sql 存储过程语句
* @param params 参数数组
* @param outParamPos 输出参数位置
* @param SqlType 输出参数类型
* @return 输出参数的值
*/
public Object excuteQuery(String sql, Object[] params,int outParamPos, int SqlType) {
Object object = null;
connnection = this.getConnection();
try {
// 调用存储过程
callableStatement = connnection.prepareCall(sql);

// 给参数赋值
if(params != null) {
for(int i = 0; i < params.length; i++) {
callableStatement.setObject(i + 1, params[i]);
}
}
// 注册输出参数
callableStatement.registerOutParameter(outParamPos, SqlType);
// 执行
callableStatement.execute();
// 得到输出参数
object = callableStatement.getObject(outParamPos);

} catch (SQLException e) {
System.out.println(e.getMessage());
} finally {
// 释放资源
closeAll();
}

return object;
}

}