springboot实战笔记(六 )----springboot整合Filter

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一 前言

 在以往的web.xml方式中，我们是通过以下形式进行配置的：

<filter>
 	<filter-name>FirstFilter</filter-name>
 	<filter-class>com.bjsxt.filter.FirstFilter</filter-class>
</filter>
<filter-mapping>
 	<filter-name>FirstFilter</filter-name>
 	<url-pattern>/first</url-pattern>
</filter-mapping>
 

但是在springboot整合Filter可以通过以下的两种方式，跟servlet很相似

•  通过注解扫描完成 Filter  组件的注册，
•  通过方法完成 Filter  组件的注册

pom.xml文件

<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/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.10.RELEASE</version>
  </parent>
  <groupId>com.bjsxt</groupId>
  <artifactId>03-spring-boot-filter</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  
  <!-- jdk1.7 -->
  <properties>
  	<java.version>1.7</java.version>
  </properties>
  
  <dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
</dependencies>
</project>

二 注解扫描方式

   1.编写Filter类 

package com.bjsxt.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;

/**
 *SpringBoot整合Filter 方式一
 */
//@WebFilter(filterName="FirstFilter",urlPatterns={"*.do","*.jsp"})
@WebFilter(filterName="FirstFilter",urlPatterns="/first")
public class FirstFilter implements Filter {

	@Override
	public void destroy() {
		// TODO Auto-generated method stub

	}
	@Override
	public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2)
			throws IOException, ServletException {
		System.out.println("进入Filter");
		arg2.doFilter(arg0, arg1);
		System.out.println("离开Filter");
	}

	@Override
	public void init(FilterConfig arg0) throws ServletException {
		// TODO Auto-generated method stub
	}
}

2.编写启动类

package com.bjsxt;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.ServletComponentScan;

/**
 *SpringBoot整合Filter 方式一
 *
 */
@SpringBootApplication
@ServletComponentScan
public class App {

	public static void main(String[] args) {
		SpringApplication.run(App.class, args);

	}

}

三 方法方式

1，编写Filter类

package com.bjsxt.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
/**
 * 
 *SpringBoot整合Filter 方式二
 *
 */
public class SecondFilter implements Filter {
	@Override
	public void destroy() {
		// TODO Auto-generated method stub
	}
	@Override
	public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2)
			throws IOException, ServletException {
		System.out.println("进入SecondFilter");
		arg2.doFilter(arg0, arg1);
		System.out.println("离开SecondFilter");
	}

	@Override
	public void init(FilterConfig arg0) throws ServletException {
		// TODO Auto-generated method stub
	}
}

2.编写启动类

package com.bjsxt;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;

import com.bjsxt.filter.SecondFilter;
import com.bjsxt.servlet.SecondServlet;

/**
 * SpringBoot整合Filter方式二
 *
 *
 */
@SpringBootApplication
public class App2 {

	public static void main(String[] args) {
		SpringApplication.run(App2.class, args);
	}
	
	/**
	 * 注册Filter
	 */
	@Bean
	public FilterRegistrationBean getFilterRegistrationBean(){
		FilterRegistrationBean bean = new FilterRegistrationBean(new SecondFilter());
		//bean.addUrlPatterns(new String[]{"*.do","*.jsp"});
		bean.addUrlPatterns("/second");
		return bean;
	}
}