自己写的程序出现的错误一直解决不了，求高手帮我看一下？ - 黑马程序员技术交流社区

for (Method m : ms) {
if (methodName.equals(m.getName())) {
//System.out.println(m.getName());
//System.out.println(rs.getObject(colName));
m.invoke(obj, new Object[] {rs.getObject(colName)});
}
}
JdbcUtils.java:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JdbcUtils {
private static String url = "jdbc:mysql://localhost:3306/userinfo";
private static String username = "root";
private static String password = "root";
private JdbcUtils(){}
static{
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static Connection getConnection() throws SQLException{
return DriverManager.getConnection(url,username,password);
}
public static void free(ResultSet rs, Statement smt,Connection conn){
if(rs != null)
try {
rs.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(smt != null)
try {
smt.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(conn != null)
try {
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}
ORMTest.java:
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
public class ORMTest {
/**
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
User user = (User) getObject(
"select id as Id, name as Name, birthday as Birthday, salary as Salary from userinfo where id=1",
User.class);
System.out.println(user.getName());
}
public static Object getObject(String sql, Class clazz) throws Exception {
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
try {
conn = JdbcUtils.getConnection();
ps = conn.prepareStatement(sql);
rs = ps.executeQuery();
String[] colNames = getColNames(rs);
Object obj = null;
Method[] ms = clazz.getMethods();
if (rs.next()) {
obj = clazz.newInstance();
for (int i = 0; i < colNames.length; i++) {
String colName = colNames[i];
String methodName = "set" + colName;
System.out.println(methodName);
System.out.println(rs.getObject(colName));
Object argument = rs.getObject(colName);
for (Method m : ms) {
if (methodName.equals(m.getName())) {
//System.out.println(m.getName());
//System.out.println(rs.getObject(colName));
m.invoke(obj, new Object[] {rs.getObject(colName)});
}
}
}
}
return obj;
} finally {
JdbcUtils.free(rs, ps, conn);
}
}
private static String[] getColNames(ResultSet rs) throws Exception {
ResultSetMetaData rsmd = rs.getMetaData();
int count = rsmd.getColumnCount();
String[] colNames = new String[count];
for (int i = 1; i <= count; i++) {
colNames[i - 1] = rsmd.getColumnLabel(i);
}
return colNames;
}
static Object getObject1(String sql, Class clazz) throws SQLException,
Exception, IllegalAccessException, InvocationTargetException {
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
try {
conn = JdbcUtils.getConnection();
ps = conn.prepareStatement(sql);
rs = ps.executeQuery();
String[] colNames = getColNames(rs);
Object object = null;
Method[] ms = clazz.getMethods();
if (rs.next()) {
object = clazz.newInstance();
for (int i = 0; i < colNames.length; i++) {
String colName = colNames[i];
String methodName = "set" + colName;
// Object value = rs.getObject(colName);
// try {
// Method m = clazz
// .getMethod(methodName, value.getClass());
// if (m != null)
// m.invoke(object, value);
// } catch (NoSuchMethodException e) {
// e.printStackTrace();
// //
// }
for (Method m : ms) {
if (methodName.equals(m.getName())) {
m.invoke(object, rs.getObject(colName));
break;
}
}
}
}
return object;
} finally {
JdbcUtils.free(rs, ps, conn);
}
}
}
User.java:
import java.util.Date;
public class User {
private int id;
private String name;
private Date birthday;
private float salary;
public User(){}
public User(String name){
this.name = name;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public float getSalary() {
return salary;
}
public void setSalary(float salary) {
this.salary = salary;
}
}

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