Java生成静态页面HMTL方法汇总
生成静态页面技术解决方案之一
转载者前言：这是一个全面的jsp动态页面静态化方案，本站的帖子静态化方案将借鉴这篇帖子中方法。向http://www.agilejava.org的single的共享精神致敬。
转帖正文：
?????? 相信很多人都希望自己的页面越快越好，最好是能静态的，提高客户访问速度。也便于搜索引擎搜索。所以，就希望我们的动态读取数据库的页面，尽可能的生成静态页面。一下系列文章，介绍一下个人的解决方案。
????? 本系列将介绍个人的一种方法，在不改变原来jsp文件的基础上，只需要加入少量的代码，就让你的新闻发布系统，很容易就完全变成静态的页面。
??????????? 本文假设你是用java 开发的web动态页面。
?????????? 第一步，加入servlet.代码如下。
????? public class ToHtml extends HttpServlet {
?????? public void service(HttpServletRequest request, HttpServletResponse response)
???????? throws ServletException, IOException {
??????? String url = "";
??????? String name = "";
??????? ServletContext sc = getServletContext();
??????? String file_name = request.getParameter("file_name");// 你要访问的jsp文件名,如index，不包括扩展名
??????? // 则你访问这个servlet时加参数.如http://localhost/test/toHtml?file_name=index
??????? url = "/" + file_name + ".jsf";// 你要生成的页面的文件名。我的扩展名为jsf .
??????? name = ConfConstants.CONTEXT_PATH+"\"+ file_name + ".htm";// 这是生成的html文件名,如index.htm.文件名字与源文件名相同。扩展名为htm
????? //ConfConstants.CONTEXT_PATH为你的应用的上下文路径。
??????? RequestDispatcher rd = sc.getRequestDispatcher(url);
??????? final ByteArrayOutputStream ōs = new ByteArrayOutputStream();
??????? final ServletOutputStream stream = new ServletOutputStream() {
???????? public void write(byte[] data, int offset, int length) {
????????? os.write(data, offset, length);
???????? }
???????? public void write(int b) throws IOException {
????????? os.write(b);
???????? }
??????? };
??????? final PrintWriter pw = new PrintWriter(new OutputStreamWriter(os));
??????? HttpServletResponse rep = new HttpServletResponseWrapper(response) {
???????? public ServletOutputStream getOutputStream() {
????????? return stream;
???????? }
???????? public PrintWriter getWriter() {
????????? return pw;
???????? }
??????? };
??????? rd.include(request, rep);
??????? pw.flush();
??????? FileOutputStream fos = new FileOutputStream(name); // 把jsp输出的内容写到xxx.htm
??????? os.writeTo(fos);
??????? fos.close();
??????? PrintWriter ōut = response.getWriter();
??????? out
????????? .print("<p align=center><font size=3 color=red>页面已经成功生成！single<br>http://www.agilejava.org/space/? 233</font></p>");
?????? }
????? }
????? 第二步、配置你的web.xml
?????? <servlet>
??????? <servlet-name>toHtml</servlet-name>
??????? <servlet-class>mj.util.html.ToHtml</servlet-class>//你的servlet的类。
?????? </servlet>
?????? <servlet-mapping>
??????? <servlet-name>toHtml</servlet-name>
??????? <url-pattern>/toHtml</url-pattern>
?????? </servlet-mapping>
????? 第三步、运行servlet。如：http://localhost:8080/test/toHtml?file_name=index
????? OK,这就在你的test项目的根目录下，生成了一个index.htm的静态文件。
????? 局限性：本文只能生成一个文件！访问一次，生成一个文件。并且生成的文件名也与原来的文件名相同。
????? 比较适合主页生成静态页面。
????? 本系列的后续文章将解决更多的问题。使之在新闻发布系统中，很容易就集成应用。
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生成静态页面技术解决方案之二
??????????? 注意：转贴本文，请加上本文链接http://www.agilejava.org/space/? ... pace_itemid_21.html?
?????????? 在上一篇文章中，生成静态页面，是有一定的局限性的。生成主页是很方便，但要生成二级页面，就不方便了。
???????????? 本文假设一个新闻发布系统。希望后台发布的，前台显示的是静态的文档。这就涉及，主页要是静态的，同时二级列表也是静态的，新闻内容也是静态的。也就是说， 在发布一篇新闻的时候，可能涉及到三个地方生成静态文档。并且，要生成一个网页，必须访问一个servlet。在大量生成静态网页的时候，
??????????? 以下方法，可以解决这些问题。
????????? 一、加入一下servelet
????????? /**
?????????? * @file_name 文件名及文件之后的参数.最好为a.jsf?fileId=aaaa
?????????? * @path 文件所在的路径.相对于根目录而言的.
?????????? * @realName文件要保存的名字
?????????? * @realPath文件要保存的真实路径。默认与文件所在的目录相同。
?????????? */
????????? public class ToHtmlPath extends HttpServlet {
?????????? public void service(HttpServletRequest request, HttpServletResponse response)
???????????? throws ServletException, IOException {
??????????? String url = "";
??????????? String name = "";
??????????? ServletContext sc = getServletContext();
??????????? String file_name = request.getParameter("file_name");// 你要访问的jsp文件,如news.jsf。
??????????? // file_name如：fileDetail.jsf?fileId=56.要是有参数， 只有一个参数。并且以参数名作为文件名。
??????????? String realName = request.getParameter("realName");// 要保存的文件名。如aaa;注意可以没有这个参数。
??????????? String path = request.getParameter("path");// 你要访问的jsp文件路径。如news。注意可以没有这个参数。
??????????? String realPath = request.getParameter("realPath");// 你要保存的文件路径,如htmlNews.注意可以没有这个参数。
??????????? // 下面确定要保存的文件名字。
??????????? if (realName == null || realName == "") {
???????????? int a = 0;
???????????? a = file_name.indexOf("=") + 1;
???????????? realName = file_name.substring(a);
???????????? if (realName.indexOf(".")>0) {
????????????? realName = file_name.substring(0, file_name.indexOf("."));
???????????? }
??????????? }
??????????? // 下面构造要访问的页面。
??????????? if (path == null || path == "") {
???????????? url = "/" + file_name;// 这是你要生成HTML的jsp文件,如
??????????? } else {
???????????? url = "/" + path + "/" + file_name;// 这是你要生成HTML的jsp文件,如
??????????? }
??????????? // 下面构造要保存的文件名，及路径。
??????????? // 1、如果有realPath，则保存在realPath下。
??????????? // 2、如果有path则保存在path下。
??????????? // 3、否则，保存在根目录下。
??????????? if (realPath == null || realPath == "") {
???????????? if (path == null || path == "") {
????????????? name = ConfConstants.CONTEXT_PATH + "\" + realName + ".htm";// 这是生成的html文件名,如index.htm.说明： ConfConstants.CONTEXT_PATH为你的上下文路径。
???????????? } else {
????????????? name = ConfConstants.CONTEXT_PATH + "\" + path + "\"
??????????????? + realName + ".htm";// 这是生成的html文件名,如index.htm.
???????????? }
??????????? } else {
???????????? name = ConfConstants.CONTEXT_PATH + "\" + realPath + "\"
?????????????? + realName + ".htm";// 这是生成的html文件名,如index.htm.
??????????? }
??????????? // 访问请求的页面，并生成指定的文件。
??????????? RequestDispatcher rd = sc.getRequestDispatcher(url);
??????????? final ByteArrayOutputStream ōs = new ByteArrayOutputStream();
??????????? final ServletOutputStream stream = new ServletOutputStream() {
???????????? public void write(byte[] data, int offset, int length) {
????????????? os.write(data, offset, length);
???????????? }
???????????? public void write(int b) throws IOException {
????????????? os.write(b);
???????????? }
??????????? };
??????????? final PrintWriter pw = new PrintWriter(new OutputStreamWriter(os));
??????????? HttpServletResponse rep = new HttpServletResponseWrapper(response) {
???????????? public ServletOutputStream getOutputStream() {
????????????? return stream;
???????????? }
???????????? public PrintWriter getWriter() {
????????????? return pw;
???????????? }
??????????? };
??????????? rd.include(request, rep);
??????????? pw.flush();
??????????? FileOutputStream fos = new FileOutputStream(name); // 把jsp输出的内容写到xxx.htm
??????????? os.writeTo(fos);
??????????? fos.close();
??????????? PrintWriter ōut = response.getWriter();
??????????? out.print("<p align=center><font size=3 color=red>success！</font></p>");
?????????? }
????????? }
????????? 二、在web.xml里面配置你的servlet
?????????? <servlet>
??????????? <servlet-name>toHtmlPath</servlet-name>
??????????? <servlet-class>mj.util.html.ToHtmlPath</servlet-class>
?????????? </servlet>
?????????? <servlet-mapping>
??????????? <servlet-name>toHtmlPath</servlet-name>
??????????? <url-pattern>/toHtmlPath</url-pattern>
?????????? </servlet-mapping>
????????? 三、写一个通用的方法， 供调用。
????????? public class CallHtml {
?????????? public static void callOnePage(String fileName, String path,
???????????? String realName, String realPath) {
??????????? try {
???????????? String str = "http://localhost:8080/test/toHtmlPath?file_name="
?????????????? + fileName + "&&path=" + path + "&&realName=" + realName
?????????????? + "&&realPath=" + realPath;
???????????? int httpResult;
???????????? URL url = new URL(str);
???????????? URLConnection connection = url.openConnection();
???????????? connection.connect();
???????????? HttpURLConnection httpURLConnection = (HttpURLConnection) connection;
???????????? httpResult = httpURLConnection.getResponseCode();
???????????? if (httpResult != HttpURLConnection.HTTP_OK) {
????????????? System.out.println("没有连接成功");
???????????? } else {
????????????? System.out.println("连接成功了 ");
???????????? }
??????????? } catch (Exception e) {
???????????? // TODO: handle exception
??????????? }
?????????? }
????????? //这个方法适当重载，就可以省去一些参数传递。
????????? }
????????? 四、在你的新闻发布save时，调用方法。
????????? 1、CallHtml.callOnePage("info.jsf?file_id=aaa",news,"", "");//将在news目录下生成一个aaa.htm的静态文件
????????? 2、CallHtml.callOnePage("newsList.jsf",news,"", "");//将在news目录下生成一个newsList.htm的静态文件,显示最新的新闻。
????????? ３、CallHtml.callOnePage("index.jsf","","", "");//生成主页。
????????? 好了，这就保持了，主页、列表、新闻内容都是最新的静态页面了。
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一个实现将动态页面转为静态的方案
1.前言
为了能深入浅出的理解这个框架的由来，我们首先来了解一下JSP解析器将我们写的JSP代码转换成的JAVA 文件的内容。
下面是一个JSP文件test.jsp
经过TOMCAT转换出的JAVA 文件test$jsp.java 内容如下：
package org.apache.jsp;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import org.apache.jasper.runtime.*;
public class test$jsp extends HttpJspBase {
??? static {
??? }
??? public testOutRedir$jsp( ) {
??? }
??? private static boolean _jspx_inited = false;
??? public final void _jspx_init() throws org.apache.jasper.runtime.JspException {
??? }
??? public void _jspService(HttpServletRequest request, HttpServletResponse? response)
??????? throws java .io.IOException, ServletException {
??????? JspFactory _jspxFactory = null;
??????? PageContext pageContext = null;
??????? HttpSession session = null;
??????? ServletContext application = null;
??????? ServletConfig config = null;
??????? JspWriter out = null;
??????? Object page = this;
??????? String? _value = null;
??????? try {
??????????? if (_jspx_inited == false) {
??????????????? synchronized (this) {
??????????????????? if (_jspx_inited == false) {
??????????????????????? _jspx_init();
??????????????????????? _jspx_inited = true;
??????????????????? }
??????????????? }
??????????? }
??????????? _jspxFactory = JspFactory.getDefaultFactory();
??????????? response.setContentType(text/html;charset=GB2312);
??????????? pageContext = _jspxFactory.getPageContext(this, request, response,
??????????????????????????? , true, 8192, true);
??????????? application = pageContext.getServletContext();
??????????? config = pageContext.getServletConfig();
??????????? session = pageContext.getSession();
??????????? out = pageContext.getOut();
??????????????? //为了节省篇幅，我删除了解释器添加的注释
??????????????? out.write(\r\n);
//上一句是由于后面的换行产生的
??????????????? out.write();
??????????????? out.write(\r\n\r\n\r\n\r\n);
??????????????? out.print( 输出 );
??????????????? out.write(\r\n\r\n\r\n\r\n);
??????? } catch (Throwable t) {
??????????? if (out != null && out.getBufferSize() != 0)
??????????????? out.clearBuffer();
??????????? if (pageContext != null) pageContext.handlePageException(t);
??????? } finally {
??????????? if (_jspxFactory != null) _jspxFactory.releasePageContext(pageContext);
??????? }
??? }
}
从上面的代码中可以清晰的看到JSP内建的几个对象（out、request、response、session、pageContext、application、config、page）是怎么产生的，懂servlet的朋友一看就能明白。
下面重点理解一下out对象，它被声明为JspWriter类型，JspWriter是一个抽象类，在包javax.servlet.jsp中可以找到它的定义。
abstract public class javax.servlet.jsp.JspWriter extends java .io.Writer{
?????? final public static int NO_BUFFER = 0;
?????? final public static int DEFAULT_BUFFER = -1;
?????? final public static int UNBOUNDED_BUFFER = -2;
?????? protected int bufferSize;
?????? protected Boolean autoFlush;
?????? protected javax.servlet.jsp.JspWriter(int arg1, boolean arg2);
??????
??? abstract public void newLine() throws IOException ;
??? abstract public void print(boolean arg0) throws IOException ;
??? abstract public void print(char arg0) throws IOException ;
??? abstract public void print(int arg0) throws IOException ;
??? abstract public void print(long arg0) throws IOException ;
??? abstract public void print(float arg0) throws IOException ;
??? abstract public void print(double arg0) throws IOException ;
??? abstract public void print(char[] arg0) throws IOException ;
??? abstract public void print(String arg0) throws IOException ;
??? abstract public void print(Object arg0) throws IOException ;
??? abstract public void println() throws IOException ;
??? abstract public void println(boolean arg0) throws IOException ;
??? abstract public void println(char arg0) throws IOException ;
??? abstract public void println(int arg0) throws IOException ;
??? abstract public void println(long arg0) throws IOException ;
??? abstract public void println(float arg0) throws IOException ;
??? abstract public void println(double arg0) throws IOException ;
??? abstract public void println(char[] arg0) throws IOException ;
??? abstract public void println(String arg0) throws IOException ;
??? abtract public void println(Object arg0) throws IOException ;
??? abstract public void clear() throws IOException ;
??? abstract public void clearBuffer() throws IOException ;
??? abstract public void flush() throws IOException ;
??? abstract public void close() throws IOException ;
??? public int getBufferSize() ;
??? abstract public int getRemaining() ;
??? public boolean isAutoFlush() ;
}
我相信当我写到这里你可能已经知道我想怎么做了。是的，来个偷天换日，继承JspWriter类，然后实现其定义的虚函数，然后把out变量替换成你自己实现的类的实例就ok了。
2.实现替换
假设
3.更新问题
下面就讨论一下如何更新生成静态文件，其实从上面实现中你可以看到，很简单的就是将生成的静态文件删除即可，至于什么时候删除，要看你的需求了。我能想到的几种情况如下
当用来生成页面的数据更新时
如果不需要很提供时时的数据可以定时更新
永远不更新
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JSP生成静态HTML页面范例
先建立一个模本页面:template.htm
<Html>
<head>
<title>###title###</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<LINK href="../Css.css" rel=stylesheet type=text/css>
</head>
<body>
<table width="500" border="0" align="center" cellpadding="0" cellspacing="2">
<tr>
<td align="center">###title###</td>
</tr>
<tr>
<td align="center">作者：###author###? </td>
</tr>
<tr>
<td>###content###
</td>
</tr>
</table>
</body>
</html>
=========================================
再写一个jsp页面: buildhtml.jsp
<%@ page contentType="text/html; charset=gb2312" import="Java .util.*,java .io.*"%>
<%
try{
String title="jsp生成静态html文件";
String content="小样，还搞不定你？";
String editer="webjxcom";
String filePath = "";
filePath = request.getRealPath("/")+"template.htm";
out.print(filePath);
String templateContent="";
FileInputStream fileinputstream = new FileInputStream(filePath);//读取模块文件
int lenght = fileinputstream.available();
byte bytes[] = new byte[lenght];
fileinputstream.read(bytes);
fileinputstream.close();
templateContent = new String(bytes);
out.print(templateContent);
templateContent=templateContent.replaceAll("###title###",title);
templateContent=templateContent.replaceAll("###content###",content);
templateContent=templateContent.replaceAll("###author###",editer);//替换掉模块中相应的地方
out.print(templateContent);
// 根据时间得文件名
Calendar calendar = Calendar.getInstance();
String fileame = String.valueOf(calendar.getTimeInMillis()) +".html";
fileame = request.getRealPath("/")+fileame;//生成的html文件保存路径
FileOutputStream fileoutputstream = new FileOutputStream(fileame);//建立文件输出流
out.print("文件输出路径:<br>");
out.print(fileame);
byte tag_bytes[] = templateContent.getBytes();
fileoutputstream.write(tag_bytes);
fileoutputstream.close();
}
catch(Exception e){
out.print(e.toString());
}
%>
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mport java .io.*;
import java .net.*;
public class Tools {
??? final static Object lock = new Object();
??? public static void makeHtml(String page, String filePath)...{
??????? makeHtml(page,filePath,"UTF-8");
??? }
??? public static void makeHtml(String page, String filePath,String chartset) {
??????? synchronized (lock) {
??????????? HttpURLConnection huc = null;
??????????? BufferedReader br = null;
??????????? BufferedWriter bw = null;
??????????? try {
??????????????? huc = (HttpURLConnection)new URL(page).openConnection();
??????????????? System.setProperty("sun.net.client.defaultConnectTimeout", "30000");
??????????????? System.setProperty("sun.net.client.defaultReadTimeout", "30000");
??????????????? huc.connect();
??????????????? InputStream stream = huc.getInputStream();
??????????????? bw = new BufferedWriter(new OutputStreamWriter (new FileOutputStream(filePath),chartset));
??????????????? br = new BufferedReader(new InputStreamReader(stream, chartset));
??????????????? String line;
??????????????? while((line = br.readLine())!= null){
?????????????????? if(line.trim().length() > 0){
??????????????????????? bw.write(line);
??????????????????????? bw.newLine();
?????????????????? }
??????????????? }
??????????? }catch (Exception e) {
??????????????? e.printStackTrace();
??????????? }finally {
??????????????? try {
??????????????????? br.close();
??????????????????? bw.close();
??????????????????? huc.disconnect();
??????????????? }catch (Exception e) {
??????????????????? e.printStackTrace();
??????????????? }
??????????? }
??????? }
}
原帖地址：http://phpjava.org/thread-340-1-1.html
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