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步骤 1 : 拓扑图点亮   
步骤 2 : 服务端跳转   
步骤 3 : ApplicationRequestDispatcher   
步骤 4 : Request   
步骤 5 : HttpProcessor   
步骤 6 : ServerJumpServlet   
步骤 7 : web.xml   
步骤 8 : TestTomcat   
步骤 9 : 比较可运行项目,快速定位问题   

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自己写一个Tomcat, 几乎使用到了除开框架外的所有Java 技术,如多线程,Socket, J2EE, 反射,Log4j, JSoup, JUnit, Html 等一整套技术栈, 从无到有,循序渐进涵盖全部74个知识点,549个开发步骤, 为竞争高薪资职位加上一个有吸引力的砝码.
增值内容,点击购买
使用爬虫已经被系统记录,请勿使用爬虫,增大封号风险。 如果是误封 ,请联系站长,谢谢
拓扑图点亮
增值内容,请先登录
自己写一个Tomcat, 几乎使用到了除开框架外的所有Java 技术,如多线程,Socket, J2EE, 反射,Log4j, JSoup, JUnit, Html 等一整套技术栈, 从无到有,循序渐进涵盖全部74个知识点,549个开发步骤, 为竞争高薪资职位加上一个有吸引力的砝码.
增值内容,点击购买
使用爬虫已经被系统记录,请勿使用爬虫,增大封号风险。 如果是误封 ,请联系站长,谢谢
步骤 3 :

ApplicationRequestDispatcher

edit
增值内容,请先登录
自己写一个Tomcat, 几乎使用到了除开框架外的所有Java 技术,如多线程,Socket, J2EE, 反射,Log4j, JSoup, JUnit, Html 等一整套技术栈, 从无到有,循序渐进涵盖全部74个知识点,549个开发步骤, 为竞争高薪资职位加上一个有吸引力的砝码.
增值内容,点击购买
使用爬虫已经被系统记录,请勿使用爬虫,增大封号风险。 如果是误封 ,请联系站长,谢谢
package cn.how2j.diytomcat.http; import java.io.IOException; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import cn.how2j.diytomcat.catalina.HttpProcessor; public class ApplicationRequestDispatcher implements RequestDispatcher { private String uri; public ApplicationRequestDispatcher(String uri) { if(!uri.startsWith("/")) uri = "/" + uri; this.uri = uri; } @Override public void forward(ServletRequest servletRequest, ServletResponse servletResponse) throws ServletException, IOException { Request request = (Request) servletRequest; Response response = (Response) servletResponse; request.setUri(uri); HttpProcessor processor = new HttpProcessor(); processor.execute(request.getSocket(), request,response); request.setForwarded(true); } @Override public void include(ServletRequest arg0, ServletResponse arg1) throws ServletException, IOException { // TODO Auto-generated method stub } }
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自己写一个Tomcat, 几乎使用到了除开框架外的所有Java 技术,如多线程,Socket, J2EE, 反射,Log4j, JSoup, JUnit, Html 等一整套技术栈, 从无到有,循序渐进涵盖全部74个知识点,549个开发步骤, 为竞争高薪资职位加上一个有吸引力的砝码.
增值内容,点击购买
使用爬虫已经被系统记录,请勿使用爬虫,增大封号风险。 如果是误封 ,请联系站长,谢谢
package cn.how2j.diytomcat.http; import cn.how2j.diytomcat.catalina.Connector; import cn.how2j.diytomcat.catalina.Context; import cn.how2j.diytomcat.catalina.Engine; import cn.how2j.diytomcat.catalina.Service; import cn.how2j.diytomcat.util.MiniBrowser; import cn.hutool.core.convert.Convert; import cn.hutool.core.convert.Converter; import cn.hutool.core.io.IoUtil; import cn.hutool.core.util.ArrayUtil; import cn.hutool.core.util.StrUtil; import cn.hutool.core.util.URLUtil; import javax.servlet.RequestDispatcher; import javax.servlet.ServletContext; import javax.servlet.http.Cookie; import javax.servlet.http.HttpSession; import java.io.IOException; import java.io.InputStream; import java.io.StringReader; import java.net.InetSocketAddress; import java.net.Socket; import java.util.*; public class Request extends BaseRequest{ private String requestString; private String uri; private Socket socket; private Context context; private String method; private String queryString; private Map<String, String[]> parameterMap; private Map<String, String> headerMap; private Cookie[] cookies; private HttpSession session; private Connector connector; private boolean forwarded; public Request(Socket socket, Connector connector) throws IOException { this.parameterMap = new HashMap(); this.headerMap = new HashMap<>(); this.socket = socket; this.connector = connector; parseHttpRequest(); if(StrUtil.isEmpty(requestString)) return; parseUri(); parseContext(); parseMethod(); if(!"/".equals(context.getPath())){ uri = StrUtil.removePrefix(uri, context.getPath()); if(StrUtil.isEmpty(uri)) uri = "/"; } parseParameters(); parseHeaders(); parseCookies(); } private void parseMethod() { method = StrUtil.subBefore(requestString, " ", false); } private void parseContext() { Service service = connector.getService(); Engine engine = service.getEngine(); context = engine.getDefaultHost().getContext(uri); if(null!=context) return; String path = StrUtil.subBetween(uri, "/", "/"); if (null == path) path = "/"; else path = "/" + path; context = engine.getDefaultHost().getContext(path); if (null == context) context = engine.getDefaultHost().getContext("/"); } private void parseHttpRequest() throws IOException { InputStream is = this.socket.getInputStream(); byte[] bytes = MiniBrowser.readBytes(is,false); requestString = new String(bytes, "utf-8"); } private void parseCookies() { List<Cookie> cookieList = new ArrayList<>(); String cookies = headerMap.get("cookie"); if (null != cookies) { String[] pairs = StrUtil.split(cookies, ";"); for (String pair : pairs) { if (StrUtil.isBlank(pair)) continue; // System.out.println(pair.length()); // System.out.println("pair:"+pair); String[] segs = StrUtil.split(pair, "="); String name = segs[0].trim(); String value = segs[1].trim(); Cookie cookie = new Cookie(name, value); cookieList.add(cookie); } } this.cookies = ArrayUtil.toArray(cookieList, Cookie.class); } private void parseUri() { String temp; temp = StrUtil.subBetween(requestString, " ", " "); if (!StrUtil.contains(temp, '?')) { uri = temp; return; } temp = StrUtil.subBefore(temp, '?', false); uri = temp; } public Context getContext() { return context; } public String getUri() { return uri; } public String getRequestString(){ return requestString; } @Override public String getMethod() { return method; } public ServletContext getServletContext() { return context.getServletContext(); } public String getRealPath(String path) { return getServletContext().getRealPath(path); } private void parseParameters() { if ("GET".equals(this.getMethod())) { String url = StrUtil.subBetween(requestString, " ", " "); if (StrUtil.contains(url, '?')) { queryString = StrUtil.subAfter(url, '?', false); } } if ("POST".equals(this.getMethod())) { queryString = StrUtil.subAfter(requestString, "\r\n\r\n", false); } if (null == queryString || 0==queryString.length()) return; queryString = URLUtil.decode(queryString); String[] parameterValues = queryString.split("&"); if (null != parameterValues) { for (String parameterValue : parameterValues) { String[] nameValues = parameterValue.split("="); String name = nameValues[0]; String value = nameValues[1]; String values[] = parameterMap.get(name); if (null == values) { values = new String[] { value }; parameterMap.put(name, values); } else { values = ArrayUtil.append(values, value); parameterMap.put(name, values); } } } } public String getParameter(String name) { String values[] = parameterMap.get(name); if (null != values && 0 != values.length) return values[0]; return null; } public Map getParameterMap() { return parameterMap; } public Enumeration getParameterNames() { return Collections.enumeration(parameterMap.keySet()); } public String[] getParameterValues(String name) { return parameterMap.get(name); } public String getHeader(String name) { if(null==name) return null; name = name.toLowerCase(); return headerMap.get(name); } public Enumeration getHeaderNames() { Set keys = headerMap.keySet(); return Collections.enumeration(keys); } public int getIntHeader(String name) { String value = headerMap.get(name); return Convert.toInt(value, 0); } public void parseHeaders() { StringReader stringReader = new StringReader(requestString); List<String> lines = new ArrayList<>(); IoUtil.readLines(stringReader, lines); for (int i = 1; i < lines.size(); i++) { String line = lines.get(i); if (0 == line.length()) break; String[] segs = line.split(":"); String headerName = segs[0].toLowerCase(); String headerValue = segs[1]; headerMap.put(headerName, headerValue); } } public String getLocalAddr() { return socket.getLocalAddress().getHostAddress(); } public String getLocalName() { return socket.getLocalAddress().getHostName(); } public int getLocalPort() { return socket.getLocalPort(); } public String getProtocol() { return "HTTP:/1.1"; } public String getRemoteAddr() { InetSocketAddress isa = (InetSocketAddress) socket.getRemoteSocketAddress(); String temp = isa.getAddress().toString(); return StrUtil.subAfter(temp, "/", false); } public String getRemoteHost() { InetSocketAddress isa = (InetSocketAddress) socket.getRemoteSocketAddress(); return isa.getHostName(); } public int getRemotePort() { return socket.getPort(); } public String getScheme() { return "http"; } public String getServerName() { return getHeader("host").trim(); } public int getServerPort() { return getLocalPort(); } public String getContextPath() { String result = this.context.getPath(); if ("/".equals(result)) return ""; return result; } public String getRequestURI() { return uri; } public StringBuffer getRequestURL() { StringBuffer url = new StringBuffer(); String scheme = getScheme(); int port = getServerPort(); if (port < 0) { port = 80; // Work around java.net.URL bug } url.append(scheme); url.append("://"); url.append(getServerName()); if ((scheme.equals("http") && (port != 80)) || (scheme.equals("https") && (port != 443))) { url.append(':'); url.append(port); } url.append(getRequestURI()); return url; } public String getServletPath() { return uri; } public Cookie[] getCookies() { return cookies; } public String getJSessionIdFromCookie() { if (null == cookies) return null; for (Cookie cookie : cookies) { if ("JSESSIONID".equals(cookie.getName())) { return cookie.getValue(); } } return null; } public HttpSession getSession() { return session; } public void setSession(HttpSession session) { this.session = session; } public Connector getConnector() { return connector; } public void setUri(String uri) { this.uri = uri; } public Socket getSocket() { return socket; } public boolean isForwarded() { return forwarded; } public void setForwarded(boolean forwarded) { this.forwarded = forwarded; } public RequestDispatcher getRequestDispatcher(String uri) { return new ApplicationRequestDispatcher(uri); } }
增值内容,请先登录
自己写一个Tomcat, 几乎使用到了除开框架外的所有Java 技术,如多线程,Socket, J2EE, 反射,Log4j, JSoup, JUnit, Html 等一整套技术栈, 从无到有,循序渐进涵盖全部74个知识点,549个开发步骤, 为竞争高薪资职位加上一个有吸引力的砝码.
增值内容,点击购买
使用爬虫已经被系统记录,请勿使用爬虫,增大封号风险。 如果是误封 ,请联系站长,谢谢
package cn.how2j.diytomcat.catalina; import cn.how2j.diytomcat.http.Request; import cn.how2j.diytomcat.http.Response; import cn.how2j.diytomcat.servlets.DefaultServlet; import cn.how2j.diytomcat.servlets.InvokerServlet; import cn.how2j.diytomcat.servlets.JspServlet; import cn.how2j.diytomcat.util.Constant; import cn.how2j.diytomcat.util.SessionManager; import cn.how2j.diytomcat.util.WebXMLUtil; import cn.hutool.core.util.*; import cn.hutool.log.LogFactory; import javax.servlet.Servlet; import javax.servlet.http.HttpSession; import java.io.IOException; import java.io.OutputStream; import java.net.Socket; public class HttpProcessor { public void execute(Socket s, Request request, Response response){ try { String uri = request.getUri(); if(null==uri) return; prepareSession(request, response); Context context = request.getContext(); String servletClassName = context.getServletClassName(uri); if(null!=servletClassName) InvokerServlet.getInstance().service(request,response); else if(uri.endsWith(".jsp")) JspServlet.getInstance().service(request,response); else DefaultServlet.getInstance().service(request,response); if(request.isForwarded()) return; if(Constant.CODE_200 == response.getStatus()){ handle200(s, request, response); return; } if(Constant.CODE_302 == response.getStatus()){ handle302(s, response); return; } if(Constant.CODE_404 == response.getStatus()){ handle404(s, uri); return; } } catch (Exception e) { LogFactory.get().error(e); handle500(s,e); } finally{ try { if(!s.isClosed()) s.close(); } catch (IOException e) { e.printStackTrace(); } } } private void handle200(Socket s, Request request, Response response) throws IOException { OutputStream os = s.getOutputStream(); String contentType = response.getContentType(); byte[] body = response.getBody(); String cookiesHeader = response.getCookiesHeader(); boolean gzip = isGzip(request, body, contentType); String headText; if (gzip) headText = Constant.response_head_200_gzip; else headText = Constant.response_head_200; headText = StrUtil.format(headText, contentType, cookiesHeader); if (gzip) body = ZipUtil.gzip(body); byte[] head = headText.getBytes(); byte[] responseBytes = new byte[head.length + body.length]; ArrayUtil.copy(head, 0, responseBytes, 0, head.length); ArrayUtil.copy(body, 0, responseBytes, head.length, body.length); os.write(responseBytes,0,responseBytes.length); os.flush(); os.close(); } private void handle404(Socket s, String uri) throws IOException { OutputStream os = s.getOutputStream(); String responseText = StrUtil.format(Constant.textFormat_404, uri, uri); responseText = Constant.response_head_404 + responseText; byte[] responseByte = responseText.getBytes("utf-8"); os.write(responseByte); } private void handle302(Socket s, Response response) throws IOException { OutputStream os = s.getOutputStream(); String redirectPath = response.getRedirectPath(); String head_text = Constant.response_head_302; String header = StrUtil.format(head_text, redirectPath); byte[] responseBytes = header.getBytes("utf-8"); os.write(responseBytes); } private void handle500(Socket s, Exception e) { try { OutputStream os = s.getOutputStream(); StackTraceElement stes[] = e.getStackTrace(); StringBuffer sb = new StringBuffer(); sb.append(e.toString()); sb.append("\r\n"); for (StackTraceElement ste : stes) { sb.append("\t"); sb.append(ste.toString()); sb.append("\r\n"); } String msg = e.getMessage(); if (null != msg && msg.length() > 20) msg = msg.substring(0, 19); String text = StrUtil.format(Constant.textFormat_500, msg, e.toString(), sb.toString()); text = Constant.response_head_500 + text; byte[] responseBytes = text.getBytes("utf-8"); os.write(responseBytes); } catch (IOException e1) { e1.printStackTrace(); } } public void prepareSession(Request request, Response response) { String jsessionid = request.getJSessionIdFromCookie(); HttpSession session = SessionManager.getSession(jsessionid, request, response); request.setSession(session); } private boolean isGzip(Request request, byte[] body, String mimeType) { String acceptEncodings= request.getHeader("Accept-Encoding"); if(!StrUtil.containsAny(acceptEncodings, "gzip")) return false; Connector connector = request.getConnector(); if (mimeType.contains(";")) mimeType = StrUtil.subBefore(mimeType, ";", false); if (!"on".equals(connector.getCompression())) return false; if (body.length < connector.getCompressionMinSize()) return false; String userAgents = connector.getNoCompressionUserAgents(); String[] eachUserAgents = userAgents.split(","); for (String eachUserAgent : eachUserAgents) { eachUserAgent = eachUserAgent.trim(); String userAgent = request.getHeader("User-Agent"); if (StrUtil.containsAny(userAgent, eachUserAgent)) return false; } String mimeTypes = connector.getCompressableMimeType(); String[] eachMimeTypes = mimeTypes.split(","); for (String eachMimeType : eachMimeTypes) { if (mimeType.equals(eachMimeType)) return true; } return false; } }
步骤 6 :

ServerJumpServlet

edit
增值内容,请先登录
自己写一个Tomcat, 几乎使用到了除开框架外的所有Java 技术,如多线程,Socket, J2EE, 反射,Log4j, JSoup, JUnit, Html 等一整套技术栈, 从无到有,循序渐进涵盖全部74个知识点,549个开发步骤, 为竞争高薪资职位加上一个有吸引力的砝码.
增值内容,点击购买
使用爬虫已经被系统记录,请勿使用爬虫,增大封号风险。 如果是误封 ,请联系站长,谢谢
package cn.how2j.javaweb; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; public class ServerJumpServlet extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException { try { request.getRequestDispatcher("hello").forward(request,response); } catch (ServletException e) { e.printStackTrace(); } } }
package cn.how2j.javaweb;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class ServerJumpServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
		try {
			request.getRequestDispatcher("hello").forward(request,response);
		} catch (ServletException e) {
			e.printStackTrace();
		}

	}
}
增值内容,请先登录
自己写一个Tomcat, 几乎使用到了除开框架外的所有Java 技术,如多线程,Socket, J2EE, 反射,Log4j, JSoup, JUnit, Html 等一整套技术栈, 从无到有,循序渐进涵盖全部74个知识点,549个开发步骤, 为竞争高薪资职位加上一个有吸引力的砝码.
增值内容,点击购买
使用爬虫已经被系统记录,请勿使用爬虫,增大封号风险。 如果是误封 ,请联系站长,谢谢
<?xml version="1.0" encoding="UTF-8"?> <web-app> <servlet> <servlet-name>HelloServlet</servlet-name> <servlet-class>cn.how2j.javaweb.HelloServlet</servlet-class> <init-param> <param-name>author</param-name> <param-value>how2j(servlet)</param-value> </init-param> <init-param> <param-name>site</param-name> <param-value>http://how2j.cn(servlet)</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>HelloServlet</servlet-name> <url-pattern>/hello</url-pattern> </servlet-mapping> <servlet> <servlet-name>ParamServlet</servlet-name> <servlet-class>cn.how2j.javaweb.ParamServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>ParamServlet</servlet-name> <url-pattern>/param</url-pattern> </servlet-mapping> <servlet> <servlet-name>HeaderServlet</servlet-name> <servlet-class>cn.how2j.javaweb.HeaderServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>HeaderServlet</servlet-name> <url-pattern>/header</url-pattern> </servlet-mapping> <servlet> <servlet-name>SetCookieServlet</servlet-name> <servlet-class>cn.how2j.javaweb.SetCookieServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>SetCookieServlet</servlet-name> <url-pattern>/setCookie</url-pattern> </servlet-mapping> <servlet> <servlet-name>GetCookieServlet</servlet-name> <servlet-class>cn.how2j.javaweb.GetCookieServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>GetCookieServlet</servlet-name> <url-pattern>/getCookie</url-pattern> </servlet-mapping> <servlet> <servlet-name>SetSessionServlet</servlet-name> <servlet-class>cn.how2j.javaweb.SetSessionServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>SetSessionServlet</servlet-name> <url-pattern>/setSession</url-pattern> </servlet-mapping> <servlet> <servlet-name>GetSessionServlet</servlet-name> <servlet-class>cn.how2j.javaweb.GetSessionServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>GetSessionServlet</servlet-name> <url-pattern>/getSession</url-pattern> </servlet-mapping> <servlet> <servlet-name>ClientJumpServlet</servlet-name> <servlet-class>cn.how2j.javaweb.ClientJumpServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>ClientJumpServlet</servlet-name> <url-pattern>/jump1</url-pattern> </servlet-mapping> <servlet> <servlet-name>ServerJumpServlet</servlet-name> <servlet-class>cn.how2j.javaweb.ServerJumpServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>ServerJumpServlet</servlet-name> <url-pattern>/jump2</url-pattern> </servlet-mapping> </web-app>
增值内容,请先登录
自己写一个Tomcat, 几乎使用到了除开框架外的所有Java 技术,如多线程,Socket, J2EE, 反射,Log4j, JSoup, JUnit, Html 等一整套技术栈, 从无到有,循序渐进涵盖全部74个知识点,549个开发步骤, 为竞争高薪资职位加上一个有吸引力的砝码.
增值内容,点击购买
使用爬虫已经被系统记录,请勿使用爬虫,增大封号风险。 如果是误封 ,请联系站长,谢谢
package cn.how2j.diytomcat.test; import cn.how2j.diytomcat.util.MiniBrowser; import cn.hutool.core.date.DateUtil; import cn.hutool.core.date.TimeInterval; import cn.hutool.core.io.IoUtil; import cn.hutool.core.util.NetUtil; import cn.hutool.core.util.StrUtil; import cn.hutool.core.util.ZipUtil; import cn.hutool.http.HttpUtil; import org.junit.Assert; import org.junit.BeforeClass; import org.junit.Test; import sun.net.www.content.text.plain; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.HttpURLConnection; import java.net.URL; import java.util.HashMap; import java.util.Map; import java.util.concurrent.LinkedBlockingQueue; import java.util.concurrent.ThreadPoolExecutor; import java.util.concurrent.TimeUnit; public class TestTomcat { private static int port = 18080; private static String ip = "127.0.0.1"; @BeforeClass public static void beforeClass() { //所有测试开始前看diy tomcat 是否已经启动了 if(NetUtil.isUsableLocalPort(port)) { System.err.println("请先启动 位于端口: " +port+ " 的diy tomcat,否则无法进行单元测试"); System.exit(1); } else { System.out.println("检测到 diy tomcat已经启动,开始进行单元测试"); } } @Test public void testHelloTomcat() { String html = getContentString("/"); Assert.assertEquals(html,"Hello DIY Tomcat from how2j.cn"); } @Test public void testTimeConsumeHtml() throws InterruptedException { ThreadPoolExecutor threadPool = new ThreadPoolExecutor(20, 20, 60, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>(10)); TimeInterval timeInterval = DateUtil.timer(); for(int i = 0; i<3; i++){ threadPool.execute(new Runnable(){ public void run() { getContentString("/timeConsume.html"); } }); } threadPool.shutdown(); threadPool.awaitTermination(1, TimeUnit.HOURS); long duration = timeInterval.intervalMs(); Assert.assertTrue(duration < 3000); } @Test public void testaIndex() { String html = getContentString("/a"); Assert.assertEquals(html,"Hello DIY Tomcat from index.html@a"); } @Test public void testbIndex() { String html = getContentString("/b/"); Assert.assertEquals(html,"Hello DIY Tomcat from index.html@b"); } @Test public void test404() { String response = getHttpString("/not_exist.html"); containAssert(response, "HTTP/1.1 404 Not Found"); } @Test public void test500() { String response = getHttpString("/500.html"); containAssert(response, "HTTP/1.1 500 Internal Server Error"); } @Test public void testaTxt() { String response = getHttpString("/a.txt"); containAssert(response, "Content-Type: text/plain"); } @Test public void testPNG() { byte[] bytes = getContentBytes("/logo.png"); int pngFileLength = 1672; Assert.assertEquals(pngFileLength, bytes.length); } @Test public void testPDF() { byte[] bytes = getContentBytes("/etf.pdf"); int pngFileLength = 3590775; Assert.assertEquals(pngFileLength, bytes.length); } @Test public void testhello() { String html = getContentString("/j2ee/hello"); Assert.assertEquals(html,"Hello DIY Tomcat from HelloServlet"); } @Test public void testJavawebHello() { String html = getContentString("/javaweb/hello"); containAssert(html,"Hello DIY Tomcat from HelloServlet@javaweb"); } @Test public void testJavawebHelloSingleton() { String html1 = getContentString("/javaweb/hello"); String html2 = getContentString("/javaweb/hello"); Assert.assertEquals(html1,html2); } @Test public void testgetParam() { String uri = "/javaweb/param"; String url = StrUtil.format("http://{}:{}{}", ip,port,uri); Map<String,Object> params = new HashMap<>(); params.put("name","meepo"); String html = MiniBrowser.getContentString(url, params, true); Assert.assertEquals(html,"get name:meepo"); } @Test public void testpostParam() { String uri = "/javaweb/param"; String url = StrUtil.format("http://{}:{}{}", ip,port,uri); Map<String,Object> params = new HashMap<>(); params.put("name","meepo"); String html = MiniBrowser.getContentString(url, params, false); Assert.assertEquals(html,"post name:meepo"); } @Test public void testheader() { String html = getContentString("/javaweb/header"); Assert.assertEquals(html,"how2j mini brower / java1.8"); } @Test public void testsetCookie() { String http = getHttpString("/javaweb/setCookie"); containAssert(http,"Set-Cookie: name=Gareen(cookie); Expires="); } @Test public void testgetCookie() throws IOException { String url = StrUtil.format("http://{}:{}{}", ip,port,"/javaweb/getCookie"); URL u = new URL(url); HttpURLConnection conn = (HttpURLConnection) u.openConnection(); conn.setRequestProperty("Cookie","name=Gareen(cookie)"); conn.connect(); InputStream is = conn.getInputStream(); String html = IoUtil.read(is, "utf-8"); containAssert(html,"name:Gareen(cookie)"); } @Test public void testSession() throws IOException { String jsessionid = getContentString("/javaweb/setSession"); if(null!=jsessionid) jsessionid = jsessionid.trim(); String url = StrUtil.format("http://{}:{}{}", ip,port,"/javaweb/getSession"); URL u = new URL(url); HttpURLConnection conn = (HttpURLConnection) u.openConnection(); conn.setRequestProperty("Cookie","JSESSIONID="+jsessionid); conn.connect(); InputStream is = conn.getInputStream(); String html = IoUtil.read(is, "utf-8"); containAssert(html,"Gareen(session)"); } @Test public void testGzip() { byte[] gzipContent = getContentBytes("/",true); byte[] unGzipContent = ZipUtil.unGzip(gzipContent); String html = new String(unGzipContent); Assert.assertEquals(html, "Hello DIY Tomcat from how2j.cn"); } @Test public void testJsp() { String html = getContentString("/javaweb/"); Assert.assertEquals(html, "hello jsp@javaweb"); } @Test public void testClientJump(){ String http_servlet = getHttpString("/javaweb/jump1"); containAssert(http_servlet,"HTTP/1.1 302 Found"); String http_jsp = getHttpString("/javaweb/jump1.jsp"); containAssert(http_jsp,"HTTP/1.1 302 Found"); } @Test public void testServerJump(){ String http_servlet = getHttpString("/javaweb/jump2"); containAssert(http_servlet,"Hello DIY Tomcat from HelloServlet"); } private byte[] getContentBytes(String uri) { return getContentBytes(uri,false); } private byte[] getContentBytes(String uri,boolean gzip) { String url = StrUtil.format("http://{}:{}{}", ip,port,uri); return MiniBrowser.getContentBytes(url,gzip); } private String getContentString(String uri) { String url = StrUtil.format("http://{}:{}{}", ip,port,uri); String content = MiniBrowser.getContentString(url); return content; } private String getHttpString(String uri) { String url = StrUtil.format("http://{}:{}{}", ip,port,uri); String http = MiniBrowser.getHttpString(url); return http; } private void containAssert(String html, String string) { boolean match = StrUtil.containsAny(html, string); Assert.assertTrue(match); } }
步骤 9 :

比较可运行项目,快速定位问题

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问答区域    
2021-02-10 request在这里不设置forwarded为true看起来也没有啥问题呀?
gjian707




问下站长,ApplicationRequestDispatcher的jforward()方法中最后需要request.setForwarded(ture),这个案例里面我看后面也没有再次用到这个request,不设置似乎也没啥问题呀???还是我哪块有所疏漏呢???谢谢谢谢
@Override
    public void forward(ServletRequest servletRequest, ServletResponse servletResponse) throws ServletException, IOException {
        Request request = (Request) servletRequest;
        Response response = (Response) servletResponse;
 
        request.setUri(uri);
         
        HttpProcessor processor = new HttpProcessor();
        processor.execute(request.getSocket(), request,response);
        request.setForwarded(true);
 
    }

							


1 个答案

how2j
答案时间:2021-02-15
HttpProcessor 里有判断啊: if(request.isForwarded()) return;



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2020-10-21 关于上一页面reponse的body,影响下一页面的body
L273




由于这里的服务器跳转,我可以理解为,当一个带有服务器跳转的Servlet或者Jsp在HttpProcess处理的过程中,调用了新的HttpProcess。即在不使用Connecter生成新socket的情况下,服务器内部进行资源访问。那么,问题来,由于这里的Response和Request都是在Connector定义的。那么,在Connector调用HttpProcess然后又在HttpProcess内执行服务器跳转的过程中,reponse是一直没有变化的。那么,我第一个执行服务器跳转的Servlet或者jsp,reponse里面产生的body数据,就会随着服务器跳转,影响接下来将被跳转的节点。也就是说,假如我a.jsp内带有一个服务器跳转语句,同时,也有一个HelloWorld。然后跳转到b.jsp,同时b.jsp里也有个Hello World但是,由于这里没有对reponse进行处理。那么,b.jsp中在浏览器输出的信息,就会是两条HelloWorld。这显然不符合事实。 所以,在reponse跳转之前,要对缓存区进行清空。以便上一界面内容不影响下一界面内容
加载中
//ApplicationRequestDispatcher中
HttpProcessor processor = new HttpProcessor();
response.resetBuffer();
processor.execute(request.getSocket(),request,response);

//Reponse中
@Override
    public void resetBuffer() {
        //处理底层buffer,设置长度为0
        this.stringWriter.getBuffer().setLength(0);
    }

							


2 个答案

wuchangkun
答案时间:2022-10-30
同理由于两次调用HttpProcess,prepareSession(request, response)这段代码导致两次设置Session,那我们保留那段Session呢
prepareSession(request, response);

how2j
答案时间:2020-10-21
哇, 你说的很有道理呢,被你发现一个bug, 赞!



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答案 或者 代码至少填写一项, 如果是自己有问题,请重新提问,否则站长有可能看不到





2020-08-21 能再解释一下如果是forwarded就不做后续处理的原因吗
2020-06-26 无论是客户端还是服务端,跳转的业务意义什么呢




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