JDBC 连接 Oracle 时，用 rs.absolute(n) 真的不如 n 次 next() 性能好

 1public static void main(String[] args) throws Exception {
 2
 3    int startCursor = 10000;   //要直接移动到的游标位置
 4    boolean stepByStep = true; //true 为 循环 next()，false 为 absolute() 定位
 5
 6    String url = "jdbc:oracle:thin:@10.128.39.23:1521:prod";
 7    oracle.jdbc.driver.OracleDriver.class.newInstance();
 8    Connection conn = DriverManager.getConnection(url, "user", "password");
 9
10    Statement stmt = null;
11    if(stepByStep){
12        stmt = conn.createStatement();
13    }else{ //要能执行 rs.absolute()，必须这么创建 Statement
14        stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
15                  ResultSet.CONCUR_READ_ONLY);
16    }
17
18    ResultSet rs = null;
19    for (int j = 1; j <= 12; j++) {
20        long start = System.currentTimeMillis();
21        rs = stmt.executeQuery("SELECT * FROM customers");
22        if(stepByStep){ //循环 next() 移动游标
23            for (int i = 0; i < startCursor; i++) {
24                rs.next();
25            }
26        }else{ //直接定位游标
27            rs.absolute(startCursor);
28        }
29
30        System.out.print(j+": 游标定位耗时："+(System.currentTimeMillis() - start)+"毫秒，");
31        start = System.currentTimeMillis();
32
33        for (int i = 0; i < 10000 && rs.next(); i++) {
34            rs.getObject(1);
35            rs.getObject(2);
36            rs.getObject(3);
37            rs.getObject(4);
38            rs.getObject(5);
39        }
40
41        System.out.println(" 获取数据耗时 :" + (System.currentTimeMillis() - start)+ " 毫秒.");
42    }
43
44    //释放资源，省去了
45}