获得数据库自动生成的主键实例：

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获得数据库自动生成的主键实例

public void insert(){

Connection con=null;

PreparedStatement st=null;

ResultSet rs=null;

//获取连接

try {

con=DBManager.getConnection();

String sql="insert into users (name,password) values (?,?)";

st=con.prepareStatement(sql);//提供了预编译的sql语句

st.setString(1, "Tom");

st.setString(2, "1234");

st.executeUpdate();

rs=st.getGeneratedKeys();//返回的是结果集,这个结果集是一个单行单列的

if(rs.next()){

System.out.println(rs.getInt(1));//输出的是id值

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

//资源释放

finally{

DBManager.release(con, st, rs);

}

附加：DBManager.java对数据库的链接

public class DBManager {

private static String username;

private static String password;

private static String url;

private static String driver;

static{

try{

InputStream in = DBManager.class.getClassLoader().getResourceAsStream("config/dbcp.properties");

Properties prop = new Properties();

prop.load(in);

driver = prop.getProperty("driverClassName");

url = prop.getProperty("url");

username = prop.getProperty("username");

password = prop.getProperty("password");

Class.forName(driver);

}catch (Exception e) {

throw new ExceptionInInitializerError(e);

}

public static Connection getConnection() throws SQLException{

return DriverManager.getConnection(url,username, password);

}

public static void release(Connection conn,Statement st,ResultSet rs){

if(rs!=null){

try{

rs.close();

}catch (Exception e) {e.printStackTrace();}

rs = null;

}

if(st!=null){

try{

st.close();

}catch (Exception e) {e.printStackTrace();}

st = null;

}

if(conn!=null){

try{

conn.close();

}catch (Exception e) {e.printStackTrace();}

conn = null;

}

获得数据库自动生成的主键实例：

public void insert(){

Connection con=null;

PreparedStatement st=null;

ResultSet rs=null;

//获取连接

try {

con=DBManager.getConnection();

String sql="insert into users (name,password) values (?,?)";

st=con.prepareStatement(sql);//提供了预编译的sql语句

st.setString(1, "Tom");

st.setString(2, "1234");

st.executeUpdate();

rs=st.getGeneratedKeys();//返回的是结果集,这个结果集是一个单行单列的

if(rs.next()){

System.out.println(rs.getInt(1));//输出的是id值

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

//资源释放

finally{

DBManager.release(con, st, rs);

}

附加：DBManager.java对数据库的链接

public class DBManager {

private static String username;

private static String password;

private static String url;

private static String driver;

static{

try{

InputStream in = DBManager.class.getClassLoader().getResourceAsStream("config/dbcp.properties");

Properties prop = new Properties();

prop.load(in);

driver = prop.getProperty("driverClassName");

url = prop.getProperty("url");

username = prop.getProperty("username");

password = prop.getProperty("password");

Class.forName(driver);

}catch (Exception e) {

throw new ExceptionInInitializerError(e);

}

public static Connection getConnection() throws SQLException{

return DriverManager.getConnection(url,username, password);

}

public static void release(Connection conn,Statement st,ResultSet rs){

if(rs!=null){

try{

rs.close();

}catch (Exception e) {e.printStackTrace();}

rs = null;

}

if(st!=null){

try{

st.close();

}catch (Exception e) {e.printStackTrace();}

st = null;

}

if(conn!=null){

try{

conn.close();

}catch (Exception e) {e.printStackTrace();}

conn = null;

}