bean:include 乱码：struts1 使用bean:include 中文乱码问题 优雅解决

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package org.apache.struts.taglib.bean;

import org.apache.struts.taglib.TagUtils;
import org.apache.struts.util.MessageResources;
import org.apache.struts.util.RequestUtils;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;

import java.io.BufferedInputStream;
import java.io.InputStreamReader;

import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

import java.util.Map;

/**
 * Define the contents of a specified intra-application request as a page
 * scope attribute of type <code>java.lang.String</code>.  If the current
 * request is part of a session, the session identifier will be included in
 * the generated request, so it will be part of the same session. <p>
 * <strong>FIXME</strong>:  In a servlet 2.3 environment, we can use a wrapped
 * response passed to RequestDispatcher.include().
 *
 * @version $Rev$ $Date: 2005-08-21 19:08:45 -0400 (Sun, 21 Aug 2005)
 *          $
 */
public class IncludeTag extends TagSupport {
    // ------------------------------------------------------------- Properties

    /**
     * Buffer size to use when reading the input stream.
     */
    protected static final int BUFFER_SIZE = 256;

    /**
     * The message resources for this package.
     */
    protected static MessageResources messages =
        MessageResources.getMessageResources(
            "org.apache.struts.taglib.bean.LocalStrings");

    /**
     * The anchor to be added to the end of the generated hyperlink.
     */
    protected String anchor = null;

    /**
     * The name of the global <code>ActionForward</code> that contains a path
     * to our requested resource.
     */
    protected String forward = null;

    /**
     * The absolute URL to the resource to be included.
     */
    protected String href = null;

    /**
     * The name of the scripting variable that will be exposed as a page scope
     * attribute.
     */
    protected String id = null;

    /**
     * The context-relative URI of the page or servlet to be included.
     */
    protected String page = null;

    /**
     * Include transaction token (if any) in the hyperlink?
     */
    protected boolean transaction = false;
    protected boolean useLocalEncoding = false;
	
    protected String useEncodingName = null;


	
    public String getAnchor() {
        return (this.anchor);
    }

    public void setAnchor(String anchor) {
        this.anchor = anchor;
    }

    public String getForward() {
        return (this.forward);
    }

    public void setForward(String forward) {
        this.forward = forward;
    }

    public String getHref() {
        return (this.href);
    }

    public void setHref(String href) {
        this.href = href;
    }

    public String getId() {
        return (this.id);
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getPage() {
        return (this.page);
    }

    public void setPage(String page) {
        this.page = page;
    }

    public boolean getTransaction() {
        return (this.transaction);
    }

    public void setTransaction(boolean transaction) {
        this.transaction = transaction;
    }

    public boolean isUseLocalEncoding() {
        return useLocalEncoding;
    }

    public void setUseLocalEncoding(boolean b) {
        useLocalEncoding = b;
    }
	
	public String getUseEncodingName() {
	    return (this.useEncodingName);
	}
	public void setUseEncodingName(String useEncodingName) {
		this.useEncodingName = useEncodingName;
	}

    // --------------------------------------------------------- Public Methods

    /**
     * Define the contents returned for the specified resource as a page scope
     * attribute.
     *
     * @throws javax.servlet.jsp.JspException if a JSP error occurs
     */
    public int doStartTag() throws JspException {
        // Set up a URLConnection to read the requested resource
        Map params =
            TagUtils.getInstance().computeParameters(pageContext, null, null,
                null, null, null, null, null, transaction);

        // FIXME - <html:link> attributes
        String urlString = null;
        URL url = null;

        try {
            urlString =
                TagUtils.getInstance().computeURLWithCharEncoding(pageContext,
                    forward, href, page, null, null, params, anchor, false,
                    useLocalEncoding);

            if (urlString.indexOf(':') < 0) {
                HttpServletRequest request =
                    (HttpServletRequest) pageContext.getRequest();

                url = new URL(RequestUtils.requestURL(request), urlString);
            } else {
                url = new URL(urlString);
            }
        } catch (MalformedURLException e) {
            TagUtils.getInstance().saveException(pageContext, e);
            throw new JspException(messages.getMessage("include.url",
                    e.toString()), e);
        }

        URLConnection conn = null;

        try {
            // Set up the basic connection
            conn = url.openConnection();
            conn.setAllowUserInteraction(false);
            conn.setDoInput(true);
            conn.setDoOutput(false);

            // Add a session id cookie if appropriate
            HttpServletRequest request =
                (HttpServletRequest) pageContext.getRequest();

            addCookie(conn, urlString, request);

            // Connect to the requested resource
            conn.connect();
        } catch (Exception e) {
            TagUtils.getInstance().saveException(pageContext, e);
            throw new JspException(messages.getMessage("include.open",
                    url.toString(), e.toString()), e);
        }

        // Copy the contents of this URL
        StringBuffer sb = new StringBuffer();

        try {
            BufferedInputStream is =
                new BufferedInputStream(conn.getInputStream());
	   //编码乱码问题的根源	
            InputStreamReader in = new InputStreamReader(is,useEncodingName); // FIXME- encodin
            char[] buffer = new char[BUFFER_SIZE];
            int n = 0;

            while (true) {
                n = in.read(buffer);

                if (n < 1) {
                    break;
                }

                sb.append(buffer, 0, n);
            }

            in.close();
        } catch (Exception e) {
            TagUtils.getInstance().saveException(pageContext, e);
            throw new JspException(messages.getMessage("include.read",
                    url.toString(), e.toString()), e);
        }

        // Define the retrieved content as a page scope attribute
        pageContext.setAttribute(id, sb.toString());

        // Skip any body of this tag
        return (SKIP_BODY);
    }

    /**
     * Add a session id cookie if appropriate. Can be overloaded to support a
     * cluster.
     *
     * @param conn
     * @param urlString
     * @param request
     * @since Struts 1.2.0
     */
    protected void addCookie(URLConnection conn, String urlString,
        HttpServletRequest request) {
        if ((conn instanceof HttpURLConnection)
            && urlString.startsWith(request.getContextPath())
            && (request.getRequestedSessionId() != null)
            && request.isRequestedSessionIdFromCookie()) {
            StringBuffer sb = new StringBuffer("JSESSIONID=");

            sb.append(request.getRequestedSessionId());
            conn.setRequestProperty("Cookie", sb.toString());
        }
    }

    /**
     * Release all allocated resources.
     */
    public void release() {
        super.release();
        anchor = null;
        forward = null;
        href = null;
        id = null;
        page = null;
        transaction = false;
    }
}

   大家可以看这个类的struts1 源码第234行，源代码上

  InputStreamReader in = new InputStreamReader(is);//FIXME- encoding

默认写法是这样的(上面都写了fixme-encoding，我就想不通怎么没有修正)，如果没有指定编码，将使用平台的默认编码

所以添加     protected String useEncodingName = null; 及其get set方法

传入我们额外增加的变量 ，InputStreamReader in = new InputStreamReader(is,useEncodingName);

完成修改之后，本地编译，然后将生成的class文件覆盖struts.jar中的原有IncludeTag.class，为了保险起见，请注意覆盖前请先备份

 

<tag>
<name>include</name>
<tagclass>org.apache.struts.taglib.bean.IncludeTag</tagclass>
<teiclass>org.apache.struts.taglib.bean.IncludeTei</teiclass>
<bodycontent>empty</bodycontent>
<attribute>
<name>anchor</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>forward</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>href</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>id</name>
<required>true</required>
<rtexprvalue>false</rtexprvalue>
</attribute>
<attribute>
<name>name</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>page</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>transaction</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>useEncodingName</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
</tag>

  修改struts-bean.tld  添加

<attribute>
<name>useEncodingName</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
这几行定义

 

<%
    if(StringUtils.isNotEmpty(zj_sjd_id)){
        String page_url = "/bgSjdMgr.do?method=showBgShouyDetail&sjdid="+ zj_sjd_id;
%>
<bean:include id="showBgShouyDetail" page="<%=page_url%>" useEncodingName="utf-8"/>
<bean:write name="showBgShouyDetail" filter="false"/>
<%
    }
%>

   在调用的时候，补上目标页面使用的编码格式，如上，我的原页面和目标页面都是utf-8，问题解决。

我开始搜这个问题的时候，网上所说的使用目标页面编码改成gbk的不优雅解决方式其实就是和默认的平台编码匹配。

本人的愚见 欢迎各路同行不吝赐教，共同探讨