利用结果集元数据将查询结果封装为map

 package it.cast.jdbc;

 import java.sql.Connection;
 import java.sql.ParameterMetaData;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.ResultSetMetaData;
 import java.sql.SQLException;
 import java.util.HashMap;
 import java.util.Map;

 public class ResultSetMetaTest {

     public static void main(String[] args) throws SQLException {

         Map<String,Object> map = read("select * from user where id=2");
         System.out.println(map);
     }

     static Map<String, Object> read(String sql) throws SQLException {

         Connection conn = null;
         PreparedStatement ps = null;
         ResultSet rs = null;

         try {
             conn = jdbcUtils.getConnection();
             ps = conn.prepareStatement(sql);
             rs = ps.executeQuery();

             ResultSetMetaData rsmd = rs.getMetaData();

             // 得出有多少列
             int count = rsmd.getColumnCount();

             String[] colNames = new String[count];

             for (int i = 1; i <= count; i++) {
                 // System.out.print(rsmd.getColumnClassName(i)+"\t");
                 // System.out.print(rsmd.getColumnName(i)+"\t");
                 // System.out.println(rsmd.getColumnLabel(i)+"\t");
                 colNames[i-1] = rsmd.getColumnName(i);
             }

             Map<String, Object> data = null;

             while (rs.next()) {
                 data = new HashMap<String, Object>();

                 for (int j = 0; j < colNames.length; j++) {
                     data.put(colNames[j], rs.getObject(colNames[j]));
                 }
             }

             return data;
         } finally {
             jdbcUtils.free(rs, ps, conn);
         }
     }
 }

ResultSetMetaTest