RESTFUL GlassFish的XML XSLT样式表的Java转换所产生的空输出

Question

我用Java编写RESTful Web服务。 的想法是“砍掉”的XML文档，并剥离了所有的联合国需要的内容（〜98％），只留下我们感兴趣的标签，同时保持文档的结构，这是如下（我不能为保密原因，实际的XML内容）：

<sear:SEGMENTS xmlns="http://www.exlibrisgroup.com/xsd/primo/primo_nm_bib" xmlns:sear="http://www.exlibrisgroup.com/xsd/jaguar/search"> 
    <sear:JAGROOT> 
     <sear:RESULT> 
     <sear:DOCSET IS_LOCAL="true" TOTAL_TIME="176" LASTHIT="9" FIRSTHIT="0" TOTALHITS="262" HIT_TIME="11"> 
      <sear:DOC SEARCH_ENGINE_TYPE="Local Search Engine" SEARCH_ENGINE="Local Search Engine" NO="1" RANK="0.086826384" ID="2347460"> 
       [ 
       <PrimoNMBib> 
        <record> 
        <display> 
         <title></title> 
        </display> 
        <sort> 
         <author></author> 
        </sort> 
        </record> 
       </PrimoNMBib> 
       ] 
      </sear:DOC> 
     </sear:DOCSET> 
     </sear:RESULT> 
    </sear:JAGROOT> 
</sear:SEGMENTS> 

当然，这仅仅是标签我们感兴趣的结构 - 有数百个标签，但它们是不相关的。

的方括号（[]）不是XML的一部分，并指示该元素是儿童的列表元素和出现多于一次的 - 每从REST式服务的搜索的匹配之一。

这就是说，包含XSLT样式表我的Java代码如下：

import java.io.StringReader; 
    import java.io.StringWriter; 

    import javax.xml.transform.Transformer; 
    import javax.xml.transform.TransformerException; 
    import javax.xml.transform.TransformerFactory; 
    import javax.xml.transform.TransformerFactoryConfigurationError; 
    import javax.xml.transform.stream.StreamResult; 
    import javax.xml.transform.stream.StreamSource; 

    public String cutXML() throws TransformerFactoryConfigurationError, TransformerException 
    { 

     String xmlSourceResource = this.xml; // where this.xml is the full XML string of structure as presented above 

     String xsltResource = 
     "<xsl:stylesheet version=\"1.0\" xmlns:xsl=\"http://www.w3.org/1999/XSL/Transform\" xmlns:sear=\"http://www.exlibrisgroup.com/xsd/jaguar/search\">" + 

     " <xsl:output method=\"xml\" version=\"1.0\" omit-xml-declaration=\"no\" encoding=\"UTF-8\" indent=\"yes\"/>" + 
     " <xsl:strip-space elements=\"*\"/>" + 

     " <sear:WhiteList>" + 
     "  <name>title</name>" + 
     "  <name>author</name>" +     
     " </sear:WhiteList>" + 

     " <xsl:template match=\"node()|@*\">" + 
     "  <xsl:copy>" + 
     "   <xsl:apply-templates select=\"node()|@*\"/>" + 
     "  </xsl:copy>" + 
     " </xsl:template>" + 

     " <xsl:template match=\"*[not(descendant-or-self::*[name()=document('')/*/sear:WhiteList/*])]\"/>" + 

     "</xsl:stylesheet>"; 

     StringWriter xmlResultResource = new StringWriter(); // where the transformed/stripped-down XML will be written 

     Transformer xmlTransformer = TransformerFactory.newInstance().newTransformer(new StreamSource(new StringReader(xsltResource))); // create transformer object with XSLT given 

     xmlTransformer.transform(new StreamSource(new StringReader(xmlSourceResource)), new StreamResult(xmlResultResource)); // transform XML with transformer and write into result StringWriter 

     return xmlResultResource.getBuffer().toString(); // return transformed XML string 

    } 

不幸的是，当我在服务器上运行它，我得到的是一个空源的空白页面，仿佛转换的结果是一个空字符串。

服务器的日志文件中第一次给了以下信息：

[#|2012-04-26T18:26:24.967+0000|INFO|glassfish3.1.2|com.sun.jersey.api.core.PackagesResourceConfig|_ThreadID=23;_ThreadName=Thread-2;|Scanning for root resource and provider classes in the packages: dk.kb.mobileservice|#] 

    [#|2012-04-26T18:26:24.969+0000|INFO|glassfish3.1.2|com.sun.jersey.api.core.ScanningResourceConfig|_ThreadID=23;_ThreadName=Thread-2;|Root resource classes found: class dk.kb.mobileservice.Middle|#] 

    [#|2012-04-26T18:26:24.970+0000|INFO|glassfish3.1.2|com.sun.jersey.api.core.ScanningResourceConfig|_ThreadID=23;_ThreadName=Thread-2;|No provider classes found.|#] 

    [#|2012-04-26T18:26:24.978+0000|INFO|glassfish3.1.2|com.sun.jersey.server.impl.application.WebApplicationImpl|_ThreadID=23;_ThreadName=Thread-2;|Initiating Jersey application, version 'Jersey: 1.11 12/09/2011 10:27 AM'|#] 

    [#|2012-04-26T18:26:25.192+0000|INFO|glassfish3.1.2|javax.enterprise.system.container.web.com.sun.enterprise.web|_ThreadID=23;_ThreadName=Thread-2;|WEB0671: Loading application [kb2] at [/kb2]|#] 

    [#|2012-04-26T18:26:25.200+0000|INFO|glassfish3.1.2|javax.enterprise.system.tools.admin.org.glassfish.deployment.admin|_ThreadID=23;_ThreadName=Thread-2;|kb2 was successfully deployed in 2,293 milliseconds.|#] 

    [#|2012-04-26T18:26:46.263+0000|SEVERE|glassfish3.1.2|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=20;_ThreadName=Thread-2;|SystemId Unknown; Line #0; Column #0; java.lang.NullPointerException |#] 

    [#|2012-04-26T18:31:09.772+0000|SEVERE|glassfish3.1.2|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=21;_ThreadName=Thread-2;|SystemId Unknown; Line #0; Column #0; java.lang.NullPointerException |#] 

，现在返回了以下问题：

[#|2012-04-27T00:05:07.731+0000|SEVERE|glassfish3.1.2|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=21;_ThreadName=Thread-2;|Error on line 1 column 1 of file:/root/webglassfish3/glassfish/domains/domain1/config/: SXXP0003: Error reported by XML parser: Content is not allowed in prolog.|#] 

    [#|2012-04-27T00:05:07.732+0000|SEVERE|glassfish3.1.2|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=21;_ThreadName=Thread-2;|Recoverable error on line 1 SXXP0003: org.xml.sax.SAXParseException: Content is not allowed in prolog.|#] 

我通过浏览器测试的XML文件，并把它改造，并它工作，所以我不认为这是XML的，也不是XSLT样式表的错误......这似乎是一个Java问题。

当我运行在GlassFish之外的整个XML上面的Java代码，我得到以下错误：

Exception in thread "main" java.lang.VerifyError: (class: GregorSamsa$0, method: test signature:   (IIIILcom/sun/org/apache/xalan/internal/xsltc/runtime/AbstractTranslet;Lcom/sun/org/apache/xml/internal/dtm/DTMAxisIterator;)Z) Incompatible type for getting or setting field 
     at GregorSamsa.applyTemplates() 
     at GregorSamsa.applyTemplates() 
     at GregorSamsa.transform() 
     at   com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet.transform(AbstractTranslet.java:609) 
     at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:729) 
     at   com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:340) 
     at XML2JSON.cutXML(XML2JSON.java:105) 
     at XML2JSON.main(XML2JSON.java:31) 

Answer 1

Content is not allowed in prolog.通常意味着你有你的XML开始前的内容。 XML解析器希望看到此XML声明：<?xml version="1.0"?>，或者如果被忽略，那么仅仅是文档元素的开始（即<sear:SEGMENTS>）

打印/日志的this.xml内容，并确认不存在任何前导空格字符或XML声明或文档元素之前的其他内容。