@Override public void filter(final ContainerRequestContext containerRequestContext) { final String requestUrl = containerRequestContext.getUriInfo().getRequestUri().toString(); if (requestUrl.endsWith("todo-or-done") || requestUrl.endsWith("change/status") || requestUrl.endsWith("change/content")) { verify(containerRequestContext, this.filterService); } }使用正则优化
时间: 2024-04-09 13:33:28 浏览: 143
要使用正则表达式优化代码,您可以尝试以下代码:
```java
@Override
public void filter(final ContainerRequestContext containerRequestContext) {
final String requestUrl = containerRequestContext.getUriInfo().getRequestUri().toString();
if (requestUrl.matches(".*/(todo-or-done|change/status|change/content)$")) {
verify(containerRequestContext, this.filterService);
}
}
```
通过使用正则表达式`".*/(todo-or-done|change/status|change/content)$"`,可以匹配以"todo-or-done"、"change/status"或"change/content"结尾的URL。这样可以避免多个endsWith()方法的调用,并且使代码更加简洁和易读。
相关问题
@Override public void filter(final ContainerRequestContext containerRequestContext) { final String requestUrl = containerRequestContext.getUriInfo().getRequestUri().toString(); if (requestUrl.endsWith(TODO_TARGET_URL) || requestUrl.endsWith(TODO_CHANGE_STATUS_URL) || requestUrl.endsWith(TODO_CHANGE_CONTENT_URL)) { verify(containerRequestContext, this.filterService); } }使用正则优化
您可以使用正则表达式来优化代码,以避免多个endsWith()方法的重复调用。下面是一个示例:
```java
@Override
public void filter(final ContainerRequestContext containerRequestContext) {
final String requestUrl = containerRequestContext.getUriInfo().getRequestUri().toString();
if (requestUrl.matches(".*/(todo|changeStatus|changeContent)$")) {
verify(containerRequestContext, this.filterService);
}
}
```
使用正则表达式`".*/(todo|changeStatus|changeContent)$"`,可以匹配以"todo"、"changeStatus"或"changeContent"结尾的URL。这样可以避免多个endsWith()方法的调用,并且使代码更加简洁和易读。
package com.sk.proxytest.proxy; import com.sk.proxytest.proxy.bean.ProxyParam; import com.sk.proxytest.proxy.bean.ProxyResult; import com.sk.proxytest.proxy.strategy.ProxyHandleService; import com.sk.proxytest.proxy.strategy.ProxyHandleStrategyFactory; import com.sk.proxytest.proxy.strategy.ProxyStrategyContext; import lombok.extern.slf4j.Slf4j; import org.apache.commons.io.IOUtils; import org.springframework.context.annotation.Configuration; import org.springframework.http.HttpEntity; import org.springframework.http.HttpMethod; import org.springframework.http.ResponseEntity; import org.springframework.web.client.RestTemplate; import javax.annotation.Resource; import javax.servlet.*; import javax.servlet.annotation.WebFilter; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.io.PrintWriter; import java.util.Map; @Slf4j @Configuration @WebFilter(filterName = "ProxyFilter", urlPatterns = "/proxy/*") public class ProxyFilter implements Filter { @Resource private RestTemplate restTemplate; @Override public void init(FilterConfig filterConfig) throws ServletException { Filter.super.init(filterConfig); } @Override public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain chain) throws IOException, ServletException { HttpServletRequest request = (HttpServletRequest) servletRequest; HttpServletResponse response = (HttpServletResponse) servletResponse; String proxyType = request.getHeader("proxy-type"); ProxyStrategyContext proxyStrategyContext = new ProxyStrategyContext(); ProxyHandleService proxyHandleService = ProxyHandleStrategyFactory.getProxyHandleStrategy(proxyType); proxyStrategyContext.setProxyHandleStrategy(proxyHandleService); ProxyResult proxyResult = proxyStrategyContext.handleProxy(new ProxyParam()); boolean flag = true; if (null != proxyResult) { PrintWriter writer = null; try { String body = IOUtils.toString(request.getInputStream()); HttpEntity<?> entity = new HttpEntity<>(body, proxyResult.getHeaders()); String url = proxyResult.getProxyUrl() + getNewUrl(request); log.info("-----------new-url:{}", url); ResponseEntity<String> responseEntity = restTemplate.exchange(url, HttpMethod.resolve(request.getMethod()), entity, String.class); response.setStatus(responseEntity.getStatusCodeValue()); writer = response.getWriter(); writer.write(responseEntity.getBody()); writer.flush(); flag = false; } catch (Exception e) { log.error("------error:{}", e); } finally { if (writer != null) { writer.close(); } } } if (flag) { chain.doFilter(request, response); } } @Override public void destroy() { Filter.super.destroy(); } //获取被代理的url和参数 private String getNewUrl(HttpServletRequest request) { String proxyUrl = request.getRequestURI().replace("/proxy", ""); Map<String, String[]> parameterMap = request.getParameterMap(); int i = 0; for (Map.Entry<String, String[]> entry : parameterMap.entrySet()) { String key = entry.getKey(); String value = entry.getValue()[0]; if (i == 0) { proxyUrl = proxyUrl + "?" + key + "=" + value; } else { proxyUrl = proxyUrl + "&" + key + "=" + value; } } return proxyUrl; } }给代码加上行注释
<think>我们被要求为给定的ProxyFilter类的Java代码添加详细的行注释。注释应该解释每一行或每个代码块的作用。注意:代码中使用了Lombok的@Slf4j注解,Spring的注解,以及Servlet的Filter。我们将逐行或逐段添加注释,解释代码的功能。代码结构:1.类注解:@Slf4j,@Configuration, @WebFilter2.字段:restTemplate3.方法:init,doFilter, destroy,以及一个私有方法getNewUrl下面开始添加注释。</think>以下是针对 `ProxyFilter` 类的详细行注释说明,结合 Servlet Filter 机制和策略模式实现进行解释:
```java
package com.sk.proxytest.proxy;
import com.sk.proxytest.proxy.bean.ProxyParam;
import com.sk.proxytest.proxy.bean.ProxyResult;
import com.sk.proxytest.proxy.strategy.ProxyHandleService;
import com.sk.proxytest.proxy.strategy.ProxyHandleStrategyFactory;
import com.sk.proxytest.proxy.strategy.ProxyStrategyContext;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.io.IOUtils;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpMethod;
import org.springframework.http.ResponseEntity;
import org.springframework.web.client.RestTemplate;
import javax.annotation.Resource;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Map;
@Slf4j // Lombok注解,自动生成日志记录器
@Configuration // 声明为Spring配置类
@WebFilter(filterName = "ProxyFilter", urlPatterns = "/proxy/*") // 定义Servlet过滤器,拦截/proxy/*路径的请求[^2]
public class ProxyFilter implements Filter { // 实现Servlet Filter接口
@Resource // 依赖注入RestTemplate实例
private RestTemplate restTemplate; // 用于发送HTTP请求的Spring工具类
@Override
public void init(FilterConfig filterConfig) throws ServletException {
Filter.super.init(filterConfig); // 过滤器初始化方法(可空实现)[^1]
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain chain)
throws IOException, ServletException {
// 将通用请求/响应对象转换为HTTP专用对象
HttpServletRequest request = (HttpServletRequest) servletRequest;
HttpServletResponse response = (HttpServletResponse) servletResponse;
// 从请求头获取代理类型标识
String proxyType = request.getHeader("proxy-type");
// 策略模式上下文初始化
ProxyStrategyContext proxyStrategyContext = new ProxyStrategyContext();
// 通过工厂获取具体代理策略实现[^1]
ProxyHandleService proxyHandleService = ProxyHandleStrategyFactory.getProxyHandleStrategy(proxyType);
proxyStrategyContext.setProxyHandleStrategy(proxyHandleService);
// 执行代理策略处理(此处ProxyParam为空,实际应传递请求参数)
ProxyResult proxyResult = proxyStrategyContext.handleProxy(new ProxyParam());
boolean flag = true; // 标记是否已处理代理请求
if (null != proxyResult) { // 策略返回有效结果时执行代理转发
PrintWriter writer = null;
try {
// 读取原始请求体
String body = IOUtils.toString(request.getInputStream());
// 构建转发请求实体(包含请求头和消息体)
HttpEntity<?> entity = new HttpEntity<>(body, proxyResult.getHeaders());
// 拼接目标URL:基础URL + 原始请求路径(移除/proxy前缀)+ 查询参数
String url = proxyResult.getProxyUrl() + getNewUrl(request);
log.info("-----------new-url:{}", url); // 记录目标URL
// 使用RestTemplate转发请求[^3]
ResponseEntity<String> responseEntity = restTemplate.exchange(
url,
HttpMethod.resolve(request.getMethod()), // 解析原始HTTP方法
entity,
String.class
);
// 设置响应状态码
response.setStatus(responseEntity.getStatusCodeValue());
writer = response.getWriter();
// 将代理响应写回客户端
writer.write(responseEntity.getBody());
writer.flush();
flag = false; // 标记代理处理完成
} catch (Exception e) {
log.error("------error:{}", e); // 记录代理异常
} finally {
if (writer != null) {
writer.close(); // 确保关闭输出流
}
}
}
// 未执行代理时继续过滤器链[^1]
if (flag) {
chain.doFilter(request, response);
}
}
@Override
public void destroy() {
Filter.super.destroy(); // 过滤器销毁方法(可空实现)[^2]
}
// 构造代理目标URL:移除/proxy前缀并附加查询参数
private String getNewUrl(HttpServletRequest request) {
String proxyUrl = request.getRequestURI().replace("/proxy", ""); // 移除URL中的/proxy前缀
Map<String, String[]> parameterMap = request.getParameterMap(); // 获取查询参数
// 拼接查询参数
int i = 0;
for (Map.Entry<String, String[]> entry : parameterMap.entrySet()) {
String key = entry.getKey();
String value = entry.getValue()[0]; // 取第一个参数值
if (i == 0) {
proxyUrl = proxyUrl + "?" + key + "=" + value; // 第一个参数前加?
} else {
proxyUrl = proxyUrl + "&" + key + "=" + value; // 后续参数前加&
}
i++;
}
return proxyUrl;
}
}
```
### 关键机制说明:
1. **过滤器拦截机制**
通过 `@WebFilter(urlPatterns = "/proxy/*")` 拦截所有以 `/proxy/` 开头的请求,符合 Servlet 过滤器规范[^1][^2]。
2. **策略模式实现**
- `ProxyHandleStrategyFactory` 根据 `proxy-type` 请求头动态选择代理策略
- `ProxyStrategyContext` 作为策略执行的上下文环境
- 符合开闭原则,便于扩展新的代理类型[^1]
3. **请求转发流程**:
```mermaid
graph TD
A[客户端请求 /proxy/api] --> B{过滤器拦截}
B --> C[解析proxy-type请求头]
C --> D[策略工厂获取处理类]
D --> E[构造目标URL和请求头]
E --> F[RestTemplate转发请求]
F --> G[返回第三方响应]
```
4. **URL 重写逻辑**
`getNewUrl()` 方法将原始 URL 从 `/proxy/api` 转换为 `/api`,并保留所有查询参数,实现路径映射。
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