URL encoding的java实例代码
时间: 2023-11-02 10:05:55 浏览: 59
好的,以下是一个简单的URL编码实例代码:
```
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
public class URLEncodingExample {
public static void main(String[] args) {
try {
String url = "https://www.example.com?search=java tutorial";
// 编码
String encodedUrl = URLEncoder.encode(url, "UTF-8");
System.out.println("编码后的URL:" + encodedUrl);
// 解码
String decodedUrl = URLDecoder.decode(encodedUrl, "UTF-8");
System.out.println("解码后的URL:" + decodedUrl);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
}
```
注意:为了防止乱码,需要在编码和解码中指定字符集为“UTF-8”。
相关问题
Hibernate的代码实例
下面是一个简单的 Hibernate 实例:
首先,我们需要建立一个数据库表来存储学生的信息。在本例中,我们将创建一个名为“students”的表,其中包含“id”、“name”和“age”列。
CREATE TABLE students (
id int(11) NOT NULL AUTO_INCREMENT,
name varchar(50) NOT NULL,
age int(11) NOT NULL,
PRIMARY KEY (id)
);
接下来,我们需要创建一个 Java 类来表示学生。在本例中,我们将创建一个名为“Student”的类,其中包含“id”、“name”和“age”属性。
public class Student {
private int id;
private String name;
private int age;
public Student() {}
public Student(String name, int age) {
this.name = name;
this.age = age;
}
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 int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "Student [id=" + id + ", name=" + name + ", age=" + age + "]";
}
}
接下来,我们需要创建一个 Hibernate 配置文件来指定数据库连接和映射信息。在本例中,我们将创建一个名为“hibernate.cfg.xml”的配置文件。
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/test</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">password</property>
<property name="hibernate.show_sql">true</property>
<mapping class="Student"/>
</session-factory>
</hibernate-configuration>
最后,我们可以编写一个简单的测试程序来测试 Hibernate 的基本功能。在本例中,我们将创建一个名为“Main”的类,该类将创建一个学生对象并将其保存到数据库中。
public class Main {
public static void main(String[] args) {
Configuration config = new Configuration().configure();
SessionFactory sessionFactory = config.buildSessionFactory();
Session session = sessionFactory.openSession();
Transaction tx = null;
try {
tx = session.beginTransaction();
Student student = new Student("Tom", 20);
session.save(student);
tx.commit();
} catch (Exception e) {
if (tx != null) {
tx.rollback();
}
e.printStackTrace();
} finally {
session.close();
sessionFactory.close();
}
}
}
运行该程序后,我们可以在数据库中看到一个名为“Tom”的学生记录已被插入到“students”表中。
java整合mybatis,springboot与mybatis整合实例详解(完美融合)
Java整合MyBatis和SpringBoot是现在Web应用开发中非常常见的一种方式,这种方式可以快速的搭建出一个基本的Web应用框架,同时也可以很方便的进行数据库操作。下面我们来详细的介绍一下Java整合MyBatis和SpringBoot的具体实现。
一、搭建SpringBoot项目
1.1 创建项目
在Eclipse或者IntelliJ IDEA中创建一个SpringBoot项目,选择maven方式,选择Web、MySQL、MyBatis等相关依赖。
1.2 配置文件
在src/main/resources目录下创建application.properties文件,添加如下配置:
```
# 数据库连接配置
spring.datasource.url=jdbc:mysql://localhost:3306/test?useSSL=false&useUnicode=true&characterEncoding=utf-8
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
# MyBatis配置
mybatis.mapper-locations=classpath:mapper/*.xml
mybatis.type-aliases-package=com.example.demo.entity
```
二、创建实体类
创建一个实体类,比如User.java,代码如下:
```
package com.example.demo.entity;
public class User {
private Integer id;
private String username;
private String password;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
```
三、创建Mapper接口
创建一个Mapper接口,比如UserMapper.java,代码如下:
```
package com.example.demo.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Mapper;
import com.example.demo.entity.User;
@Mapper
public interface UserMapper {
List<User> findAll();
User findById(Integer id);
void insert(User user);
void update(User user);
void delete(Integer id);
}
```
四、创建Mapper.xml文件
在src/main/resources/mapper目录下创建UserMapper.xml文件,代码如下:
```
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.demo.mapper.UserMapper">
<resultMap id="BaseResultMap" type="com.example.demo.entity.User">
<id column="id" property="id" />
<result column="username" property="username" />
<result column="password" property="password" />
</resultMap>
<select id="findAll" resultMap="BaseResultMap">
SELECT * FROM user
</select>
<select id="findById" parameterType="java.lang.Integer" resultMap="BaseResultMap">
SELECT * FROM user WHERE id = #{id}
</select>
<insert id="insert" parameterType="com.example.demo.entity.User">
INSERT INTO user (username, password) VALUES (#{username}, #{password})
</insert>
<update id="update" parameterType="com.example.demo.entity.User">
UPDATE user SET username = #{username}, password = #{password} WHERE id = #{id}
</update>
<delete id="delete" parameterType="java.lang.Integer">
DELETE FROM user WHERE id = #{id}
</delete>
</mapper>
```
五、创建Service
创建一个Service,比如UserService.java,代码如下:
```
package com.example.demo.service;
import java.util.List;
import com.example.demo.entity.User;
public interface UserService {
List<User> findAll();
User findById(Integer id);
void save(User user);
void update(User user);
void delete(Integer id);
}
```
创建一个ServiceImpl,比如UserServiceImpl.java,代码如下:
```
package com.example.demo.service.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.example.demo.entity.User;
import com.example.demo.mapper.UserMapper;
import com.example.demo.service.UserService;
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserMapper userMapper;
@Override
public List<User> findAll() {
return userMapper.findAll();
}
@Override
public User findById(Integer id) {
return userMapper.findById(id);
}
@Override
public void save(User user) {
userMapper.insert(user);
}
@Override
public void update(User user) {
userMapper.update(user);
}
@Override
public void delete(Integer id) {
userMapper.delete(id);
}
}
```
六、创建Controller
创建一个Controller,比如UserController.java,代码如下:
```
package com.example.demo.controller;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import com.example.demo.entity.User;
import com.example.demo.service.UserService;
@RestController
@RequestMapping("/users")
public class UserController {
@Autowired
private UserService userService;
@RequestMapping(value = "/", method = RequestMethod.GET)
public List<User> findAll() {
return userService.findAll();
}
@RequestMapping(value = "/{id}", method = RequestMethod.GET)
public User findById(@PathVariable Integer id) {
return userService.findById(id);
}
@RequestMapping(value = "/", method = RequestMethod.POST)
public void save(@RequestBody User user) {
userService.save(user);
}
@RequestMapping(value = "/", method = RequestMethod.PUT)
public void update(@RequestBody User user) {
userService.update(user);
}
@RequestMapping(value = "/{id}", method = RequestMethod.DELETE)
public void delete(@PathVariable Integer id) {
userService.delete(id);
}
}
```
七、启动项目
在Eclipse或者IntelliJ IDEA中启动SpringBoot项目,启动成功后就可以通过http://localhost:8080/users/访问到我们创建的接口了。
以上就是Java整合MyBatis和SpringBoot的具体实现,希望对大家有所帮助。