JDBC增删改查和查唯一的完整代码解析

第一部分代码（实体类）

package com.wf.entity;
public class Hehe{
private int hehe_id;
private String hehe_name;
private String hehe_gender;
public int getHehe_id(){
return hehe_id;
}
public void setHehe_id(int heheId){
hehe_id=heheId;
}
public String getHehe_name() {
return hehe_name;
}
public void setHehe_name(String heheName) {
hehe_name = heheName;
}
public String getHehe_gender() {
return hehe_gender;
}
public void setHehe_gender(String heheGender) {
hehe_gender = heheGender;
}
}

第二部分 BaseDao（增删改查和查唯一）

package com.wf.dao;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class BaseDao{
protected static final String DRIVER="com.mysql.jdbc.Driver";
protected static final String URL="mysql://localhost:3306/mysql";
protected static final String USER="root";
protected static final String PASSWORD="******";
protected Connection connection=null;
protected PreparedStatement preparedStatement=null;
protected ResultSet resultSet =null;
protected void getconnection() throws ClassNotFoundException, SQLException{
  Class.forName(DRIVER);
  this.connection =DriverManager.getconnection (URL,USER,PASSWORD);
}
/**
* 通用的增删改方法
* @param sql SQL语句
* @param params 参数数组
* @return 受影响的行数
*/
protected int executeUpdate(String sql ,String[]params){
int result=-1;
try {
this.getconnection();
this.preparedStatement=this.connection.prepareStatement(sql);
if(null!=params){
for (int i = 0; i < params.length; i++) {
this.preparedStatement.setString(i+1, params[i]);
}
}
result= this.preparedStatement.executeUpdate();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}finally{
this.close();
}
return result;
}
/**
* 查询结果集的方法
* @param sql
* @param params
*/
protected void executeQuery(String sql,String[]params){
try {
this.getconnection();
this.preparedStatement=this.connection.prepareStatement(sql);
if(null!=params){
for (int i = 0; i < params.length; i++) {
this.preparedStatement.setString(i+1, params[i]);
}
}
this.resultSet=this.preparedStatement.executeQuery();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}

/**
* 查询唯一的结果
* @return Object
*/
protected Object executeQueryUnique(String sql,String[]params){
Object object=null;
try {
this.getconnection();
this.preparedStatement=this.connection.prepareStatement(sql);
if(null!=params){
for (int i = 0; i < params.length; i++) {
this.preparedStatement.setString(i+1, params[i]);
}
}
this.resultSet=this.preparedStatement.executeQuery();
if(this.resultSet.next())
object=this.resultSet.getObject(1);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
return object;
}
protected void close(){
try {
if(null!=this.resultSet)
this.resultSet.close();
if(null!=this.preparedStatement)
this.preparedStatement.close();
if(null!=this.connection)
this.connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}

第三部分 HeheDao

package com.wf.dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import com.wf.entity.Hehe;
public class HeheDao extends BaseDao{
public boolean insert(Hehe hehe){
String sql="insert into hehe(hehe_name,hehe_gender) values(?,?)" ;
String []params=new String[]{hehe.getHehe_name(),hehe.getHehe_gender()};
return this.executeUpdate(sql, params)>0? true:false;
}

第四部分 测试Test_BaseDao_Insert

package com.wf.test;
import com.wf.dao.HeheDao;
import com.wf.entity.Hehe;
public class Test_BaseDao_Insert {
public static void main(String[] args) {
Hehe hehe=new Hehe();
hehe.setHehe_name("个");
hehe.setHehe_gender("b");
HeheDao _hd=new HeheDao();
if(_hd.insert(hehe))
System.out.println("成功!");
else
System.out.println("失败!");
}
}