java跨域问题
javaWeb项目跨域问题解决方案：
1.简单的servlet项目
1.配置一个filter过滤器，过滤所有的请求，并且设置响应头
package Filter; import javax.servlet.*; import javax.servlet.http.HttpServletResponse; import java.io.IOException; /*自定义拦截器 用于给每个都加上跨域的头*/ public class CORSFilter implements Filter { @Override public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { //变成http的 HttpServletResponse resp = (HttpServletResponse) response; // 添加参数，允许任意domain访问 resp.setContentType("text/html;charset=UTF-8"); //禁用缓存，确保网页信息是最新数据 resp.setHeader("Pragma","No-cache"); resp.setHeader("Cache-Control","no-cache"); resp.setHeader("Access-Control-Allow-Origin", "*"); resp.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, HEAD, DELETE, PUT"); resp.setHeader("Access-Control-Max-Age", "3600"); resp.setHeader("Access-Control-Allow-Headers", "X-Requested-With, Content-Type, Authorization, Accept, Origin, User-Agent, Content-Range, Content-Disposition, Content-Description"); resp.setDateHeader("Expires", -10); chain.doFilter(request, resp); } public void init(FilterConfig filterConfig) {} public void destroy() {} }
2.在web.xml中声明该过滤器（注意：最好放在最前面）
<filter>
<filter-name>cors</filter-name>
<filter-class>Filter.CORSFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>cors</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
3.然后就可以直接解决跨域问题了
2.使用springMVC下的跨域问题解决方案
1.先把整个springMVC项目搭建起来
1.1在pom.xml中引入maven依赖
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <packaging>war</packaging> <name>smart_blog</name> <groupId>com.kylin</groupId> <artifactId>smart_blog</artifactId> <version>1.0-SNAPSHOT</version> <build> <plugins> <plugin> <groupId>org.mortbay.jetty</groupId> <artifactId>maven-jetty-plugin</artifactId> <version>6.1.7</version> <configuration> <connectors> <connector implementation="org.mortbay.jetty.nio.SelectChannelConnector"> <port>8888</port> <maxIdleTime>30000</maxIdleTime> </connector> </connectors> <webAppSourceDirectory>${project.build.directory}/${pom.artifactId}-${pom.version}</webAppSourceDirectory> <contextPath>/</contextPath> </configuration> </plugin> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <configuration> <source>6</source> <target>6</target> </configuration> </plugin> </plugins> </build> <dependencies> <!-- junit --> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12-beta-3</version> <scope>test</scope> </dependency> <!-- log4j --> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.17</version> </dependency> <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <!-- spring 的基本依赖 开始 --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-expression</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aspects</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>4.3.18.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>4.3.18.RELEASE</version> </dependency> <!-- spring 的基本依赖 结束 --> <!-- https://mvnrepository.com/artifact/javax.servlet.jsp/javax.servlet.jsp-api --> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>javax.servlet.jsp-api</artifactId> <version>2.2.1</version> <scope>provided</scope> </dependency> <!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api --> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency> <!-- https://mvnrepository.com/artifact/com.google.code.gson/gson --> <dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> <version>2.2.4</version> </dependency> </dependencies> </project>
1.2编写springMVC的核心配置文件
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd"> <!-- Enables the Spring MVC @Controller programming model --> <mvc:annotation-driven /> <context:component-scan base-package="com.kylin.Controller" /> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/" /> <property name="suffix" value=".jsp" /> </bean> </beans>
1.3在web.xml中进行基本配置
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <filter> <filter-name>CORSFilter</filter-name> <filter-class>com.kylin.Filter.CORSFilter</filter-class> </filter> <filter-mapping> <filter-name>CORSFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <!--拦截器的配置--> <!--前端控制器的配置--> <servlet> <servlet-name>springMVC</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <!--配置核心配置文件的位置--> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring/springMVC.xml</param-value> </init-param> <!--随服务器启动而启动--> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>springMVC</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app>
2.编写过滤器CORSFilter来处理跨域问题
package com.kylin.Filter; import javax.servlet.*; import javax.servlet.http.HttpServletResponse; import java.io.IOException; /*自定义拦截器 用于给每个都加上跨域的头*/ public class CORSFilter implements Filter { @Override public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { //变成http的 HttpServletResponse resp = (HttpServletResponse) response; // 添加参数，允许任意domain访问 resp.setContentType("text/html;charset=UTF-8"); //禁用缓存，确保网页信息是最新数据 resp.setHeader("Pragma","No-cache"); resp.setHeader("Cache-Control","no-cache"); resp.setHeader("Access-Control-Allow-Origin", "*"); resp.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, HEAD, DELETE, PUT"); resp.setHeader("Access-Control-Max-Age", "3600"); resp.setHeader("Access-Control-Allow-Headers", "X-Requested-With, Content-Type, Authorization, Accept, Origin, User-Agent, Content-Range, Content-Disposition, Content-Description"); resp.setDateHeader("Expires", -10); chain.doFilter(request, resp); } public void init(FilterConfig filterConfig) {} public void destroy() {} }
3.在web.xml中声明该过滤器(注意：位置最好放在最前面)
由于web.xml中上面已经有了，就不再重复拷贝代码
4.就能正常的解决跨域问题
下面附上项目的目录结构：
附上前端vue框架的代码：
ps：前端vue框架刚刚学，很多东西不懂~别介意
附上项目目录：
1.在config/index.js中配置代理
2.在router/index.js中配置路由
3.在组件中使用axios来发送post请求
src/components/Login.vue
<template>
<div class="Login">
<input type="tel" placeholder="innput your phone...." v-model="phone">
<input type="password" placeholder="input your password" v-model="password">
<button @click="postMethod">提交</button>
</div>
</template>
<script>
import axios from 'axios'
export default {
name: 'Login',
data () {
return {
phone:'',
password:'',
}
},
methods:{
postMethod:function(){
axios.post('http://192.168.253.13:8080/smart_blog/user',{
phone:this.phone,
password:this.password,
})
.then(function(res){
console.log(res)
// alert(res.data.message)
alert(res.data.status)
})
.catch(function(err){
console.log(err)
})
}
}
}
</script>
<!-- Add "scoped" attribute to limit CSS to this component only -->
<style scoped>
</style>
4.打开vue项目所在的目录，输入npm start命令启动项目即可
5.开心的实现前后端分离~~~~~
