该获取主键并不是绝对的，也和具体的数据库实现的驱动有关。
package cn.itcast.jdbc; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import org.junit.Test; /** * 测试JDBC中的几个其他API */ public class OtherApi { /** * 测试create方法 * @throws SQLException */ @Test public void testCreate() throws SQLException { System.out.println(create()); } /** * 测试从数据库读取数据 * @throws SQLException * @throws InterruptedException */ @Test public void testRead() throws SQLException, InterruptedException { read(); } /** * 读取数据库中的数据 * @throws SQLException * @throws InterruptedException */ static void read() throws SQLException, InterruptedException { Connection conn = null; Statement st = null; ResultSet rs = null; try { //建立连接 conn = JdbcUtils.getConnection(); //创建语句 st = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE); //执行语句 rs = st.executeQuery("select id, name, money, birthday from user where id < 5"); //处理结果 while(rs.next()) { int id = rs.getInt("id"); System.out.println("show" + id + "..."); Thread.sleep(10000); System.out.println(id +"\t" + rs.getObject("name") + "\t" + rs.getObject("birthday") + "\t" + rs.getObject("money")); } } finally { JdbcUtils.free(rs, st, conn); } } /** * 向数据库中插入语句 * @return * @throws SQLException */ static int create() throws SQLException { Connection conn = null; PreparedStatement ps = null; ResultSet rs = null; try { //建立连接 conn = JdbcUtils.getConnection(); //创建语句 String sql = "insert into user(name,birthday, money) values ('name2 gk', '1987-01-01', 400) "; //通过传入第二个参数,就会产生主键返回给我们 ps = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS); ps.executeUpdate(); //返回的结果集中包含主键,注意：主键还可以是UUID, //复合主键等,所以这里不是直接返回一个整型 rs = ps.getGeneratedKeys(); int id = 0; if(rs.next()) { id = rs.getInt(1); } return id; } finally{ JdbcUtils.free(rs, ps, conn); } } }