增加jdbc工具类

zheng-common/src/main/java/com/zheng/common/util/JdbcUtil.java

@@ -0,0 +1,89 @@
+package com.zheng.common.util;
+
+import java.sql.*;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * JDBC工具类
+ * Created by ZhangShuzheng on 2017/1/10.
+ */
+public class JdbcUtil {
+
+	// 定义数据库的链接
+	private Connection conn;
+	// 定义sql语句的执行对象
+	private PreparedStatement pstmt;
+	// 定义查询返回的结果集合
+	private ResultSet rs;
+
+	// 初始化
+	public JdbcUtil(String driver, String url, String username, String password) {
+		try {
+			Class.forName(driver);
+			System.out.println("注册驱动成功!!");
+			conn = DriverManager.getConnection(url, username, password);
+			System.out.println("数据库连接成功");
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+	}
+
+	// 更新数据
+	public boolean updateByParams(String sql, List params) throws SQLException {
+		// 影响行数
+		int result = -1;
+		pstmt = conn.prepareStatement(sql);
+		int index = 1;
+		// 填充sql语句中的占位符
+		if (null != params && !params.isEmpty()) {
+			for (int i = 0; i < params.size(); i ++) {
+				pstmt.setObject(index ++, params.get(i));
+			}
+		}
+		result = pstmt.executeUpdate();
+		return result > 0 ? true : false;
+	}
+
+	// 查询多条记录
+	public List<Map> selectByParams(String sql, List params) throws SQLException {
+		List<Map> list = new ArrayList<> ();
+		int index = 1;
+		pstmt = conn.prepareStatement(sql);
+		if (null != params && !params.isEmpty()) {
+			for (int i = 0; i < params.size(); i ++) {
+				pstmt.setObject(index++, params.get(i));
+			}
+		}
+		rs = pstmt.executeQuery();
+		ResultSetMetaData metaData = rs.getMetaData();
+		int cols_len = metaData.getColumnCount();
+		while (rs.next()) {
+			Map map = new HashMap();
+			for (int i = 0; i < cols_len; i ++) {
+				String cols_name = metaData.getColumnName(i + 1);
+				Object cols_value = rs.getObject(cols_name);
+				if (null == cols_value) {
+					cols_value = "";
+				}
+				map.put(cols_name, cols_value);
+			}
+			list.add(map);
+		}
+		return list;
+	}
+
+	// 释放连接
+	public void release() {
+		try {
+			if (null != rs) rs.close();
+			if (null != pstmt) pstmt.close();
+			if (null != conn) conn.close();
+		} catch (SQLException e) {
+			e.printStackTrace();
+		}
+	}
+
+}