struts的include标签的修改，使支持http形式
本文需要读者对struts的标签源码比较熟悉。
由于公司的web应用根据不同的业务形式采用的独立部署。使各个业务的耦合度降低。使业务更加的灵活。
但是面临的是业务WEB_A应用需要调用业务WEB_B应用的页面。
1:ajax的形式。使用下来效果也不错，满足了要求。
但是面临的问题也来了。最最重要的是SEO，由于这块是异步加载的。由于WEB_A的主体是WEB_B所以，所以WEB_A基本上是页面无变动的。2:action中用java拿到页面的IO流。输出到页面上。但是，这样的情况下，就会使开发要写多余的重复的代码。3:代码、页面写在WEB_A上。但是这样的话，就使的开发需要维护两个业务工程。4:如有其他方案请联系我：）
后来在研究struts的s:include标签的时候，感觉也可以用自定义标签来解决类似问题。
附上代码：
中间的标签的配置省略了。
/** * 获取http请求内容 * * @author shanzhu * @version 1.0 2011-9-15 */package org.apache.struts2.views.jsp;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.struts2.components.Component;import org.apache.struts2.components.IncludeHttp;import com.opensymphony.xwork2.util.ValueStack;public class IncludeHttpTag extends ComponentTagSupport{ /** * */ private static final long serialVersionUID = 4811111257523224901L; protected String value; protected String charset; //编码 protected int conntimeout; protected int requtimeout; public Component getBean(ValueStack stack, HttpServletRequest req, HttpServletResponse res) { return new IncludeHttp(stack, req, res); } protected void populateParams() { super.populateParams(); ((IncludeHttp) component).setValue(value); ((IncludeHttp) component).setCharset(charset); ((IncludeHttp) component).setConntimeout(conntimeout); ((IncludeHttp) component).setRequtimeout(requtimeout); } public void setValue(String value) { this.value = value; } public void setCharset(String charset) { this.charset = charset; } public void setConntimeout(int conntimeout) { this.conntimeout = conntimeout; } public void setRequtimeout(int requtimeout) { this.requtimeout = requtimeout; }}/** * includehttp的时候。处理value是http开头。 * 当使用这个标签的时候，会根据标签内的值取得url的io，写在页面上 * * @author shanzhu * @version 1.0 2011-9-15 */package org.apache.struts2.components;import java.io.BufferedReader;import java.io.InputStreamReader;import java.io.Writer;import java.net.HttpURLConnection;import java.net.URL;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import java.util.Map;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.apache.struts2.StrutsConstants;import org.apache.struts2.components.Component;import org.apache.struts2.views.annotations.StrutsTag;import org.apache.struts2.views.annotations.StrutsTagAttribute;import com.opensymphony.xwork2.inject.Inject;import com.opensymphony.xwork2.util.ValueStack;@StrutsTag(name="IncludeHttp", tldTag+ "(result of http context)")public class IncludeHttp extends Component { private final String URL_AND = "&"; private final String URL_DENGYU = "="; private final String URL_WENHAO = "?"; private final String STR_KONG = ""; private static final Log _log = LogFactory.getLog(IncludeHttp.class); protected String value; //url protected String charset; //以charset编码去取得远程的io protected int conntimeout; //超时时间 protected int requtimeout; //超时时间 private String wenhao ; private String strParmaeters = ""; private HttpServletRequest req; private HttpServletResponse res; private static String defaultEncoding; public IncludeHttp(ValueStack stack, HttpServletRequest req, HttpServletResponse res) { super(stack); this.req = req; this.res = res; } @Inject(StrutsConstants.STRUTS_I18N_ENCODING) public static void setDefaultEncoding(String encoding) { defaultEncoding = encoding; } public boolean end(Writer writer, String body) { checkURL(); value = value + this.wenhao + strParmaeters; String webContext = GetWebContent(value,charset,conntimeout,requtimeout); return super.end(writer, webContext); } /** * 对url进行检查拼装 */ private void checkURL(){ checkUrlSameStatus(); checkParmater(); } /** * 对？进行检查 */ private void checkUrlSameStatus(){ if (this.value.indexOf(this.URL_WENHAO)>-1) { wenhao = STR_KONG; }else { wenhao = this.URL_WENHAO; } } /** * 对参数进行检查 */ private void checkParmater(){ if (this.parameters==null || this.parameters.size()<=0) { strParmaeters = STR_KONG; }else { Iterator<?> it = parameters.entrySet().iterator(); while (it.hasNext()) { Map.Entry entry = (Map.Entry) it.next(); if (strParmaeters.indexOf("&")>-1) { strParmaeters = strParmaeters + this.URL_AND+entry.getKey() + this.URL_DENGYU + ((List)entry.getValue()).get(0); }else { strParmaeters = strParmaeters +entry.getKey() + this.URL_DENGYU + ((List)entry.getValue()).get(0); } } } } @StrutsTagAttribute(description="The jsp/servlet output to include", required=true) public void setValue(String value) { this.value = value; } /** * 取得includehttp标签内使用的parameter标签的值 */ @SuppressWarnings("unchecked") public void addParameter(String key, Object value) { // don't use the default implementation of addParameter, // instead, include tag requires that each parameter be a list of objects, // just like the HTTP servlet interfaces are (String[]) if (value != null) { List currentValues = (List) parameters.get(key); if (currentValues == null) { currentValues = new ArrayList(); parameters.put(key, currentValues); } currentValues.add(value); } } public void setCharset(String charset) { if (isEmpty(charset)) { charset = "utf-8"; } this.charset = charset; } public void setConntimeout(int conntimeout) { if (conntimeout<=0) { conntimeout = 3000; } this.conntimeout = conntimeout; } public void setRequtimeout(int requtimeout) { if (requtimeout<=0) { requtimeout = 3000; } this.requtimeout = requtimeout; } boolean isEmpty(String str){ if (str == null || "".equals(str)) { return true; } return false; } /* * 取得指定URL的Web内容 */ public static String GetWebContent(final String theURL,final String charset,final int connTimeout,final int requTimeout) { String sTotalString = ""; URL l_url = null; HttpURLConnection l_connection = null; java.io.InputStream l_urlStream = null; BufferedReader l_reader = null; try { l_url = new URL(theURL); l_connection = (HttpURLConnection) l_url.openConnection(); l_connection.setConnectTimeout(connTimeout); // 加入取内容超时处理 l_connection.setReadTimeout(requTimeout); l_connection.connect(); l_urlStream = l_connection.getInputStream(); l_reader = new BufferedReader(new InputStreamReader(l_urlStream,charset)); int buffer_size = 1024; char[] buffer = new char[buffer_size]; StringBuffer sb = new StringBuffer(); int readcount = 0; while ((readcount = l_reader.read(buffer, 0, buffer_size)) > 0) { sb.append(buffer, 0, readcount); } sTotalString = sb.toString(); l_reader.close(); l_urlStream.close(); l_connection.disconnect(); } catch (Exception e) { System.out.println("error: exception in WebUtil: " + e.toString() + ":" + theURL); } finally { if (l_reader != null) { try { l_reader.close(); } catch (Exception e) { } } if (l_urlStream != null) { try { l_urlStream.close(); } catch (Exception e) { } } if (l_connection != null) { try { l_connection.disconnect(); } catch (Exception e) { } } } if (sTotalString==null) { sTotalString = ""; } return sTotalString; } }
2 楼 mozhenghua 2011-09-16 刚哥加油！！！！ 3 楼 lwg2001s 2011-09-16 牛B啊，山猪... 4 楼 jiangfangyuan 2011-09-16 nb。。刚哥 顶起 5 楼 Sweblish 2011-09-18 仔细拜读中。。。。