【发布时间】:2016-04-05 14:18:04
【问题描述】:
我构建 saxon9-7-0-4source.zip 并尝试在基于以下 xml 的 dom4j 文档中执行 xPath .//item[@name='entry']//property[matches(@value,'test[0-9]{1,2}$')]/..:
<root>
<item name="abc">
<iitem>
<property value="test"/>
</iitem>
</item>
<item name="entry">
<iitem>
<property value="test"/>
</iitem>
<iitem>
<iiitem>
<property value="test12"/>
</iiitem>
</iitem>
<iitem>
<property value="123"/>
</iitem>
</item>
</root>
xPath 符合我的预期,我在 http://www.qutoric.com/xslt/analyser/xpathtool.html 在线测试它
但是如果我在我的 java 代码中尝试同样的方法
Processor proc = new Processor(false);
proc.getUnderlyingConfiguration().registerExternalObjectModel(new DOM4JObjectModel());
DocumentBuilder db = proc.newDocumentBuilder();
XdmNode xdmDoc = db.wrap(doc4j);
XPathCompiler xpath = proc.newXPathCompiler();
String path=".//item[@name='entry']//property[matches(@value,'test[0-9]{1,2}$')]/..";
XPathExecutable viewPath = xpath.compile(path);
我在线程“main”中收到意外错误异常
Exception in thread "main" java.lang.Error: Unresolved compilation problem:
Cannot instantiate the type SystemFunctionCall
at net.sf.saxon.functions.SystemFunction.makeFunctionCall(SystemFunction.java:94)
at net.sf.saxon.functions.RegexFunction.makeFunctionCall(RegexFunction.java:69)
at net.sf.saxon.functions.RegexFunctionSansFlags.makeFunctionCall(RegexFunctionSansFlags.java:49)
at net.sf.saxon.functions.SystemFunctionLibrary.bind(SystemFunctionLibrary.java:91)
at net.sf.saxon.functions.FunctionLibraryList.bind(FunctionLibraryList.java:105)
at net.sf.saxon.expr.parser.XPathParser.parseFunctionCall(XPathParser.java:3015)
at net.sf.saxon.expr.parser.XPathParser.parseBasicStep(XPathParser.java:2005)
at net.sf.saxon.expr.parser.XPathParser.parseStepExpression(XPathParser.java:1890)
at net.sf.saxon.expr.parser.XPathParser.parseRelativePath(XPathParser.java:1815)
at net.sf.saxon.expr.parser.XPathParser.parsePathExpression(XPathParser.java:1777)
at net.sf.saxon.expr.parser.XPathParser.parseSimpleMappingExpression(XPathParser.java:1791)
at net.sf.saxon.expr.parser.XPathParser.parseUnaryExpression(XPathParser.java:1666)
at net.sf.saxon.expr.parser.XPathParser.parseExprSingle(XPathParser.java:653)
at net.sf.saxon.expr.parser.XPathParser.parseExpression(XPathParser.java:592)
at net.sf.saxon.expr.parser.XPathParser.parsePredicate(XPathParser.java:1958)
at net.sf.saxon.expr.parser.XPathParser.parseStepExpression(XPathParser.java:1900)
at net.sf.saxon.expr.parser.XPathParser.parseRelativePath(XPathParser.java:1820)
at net.sf.saxon.expr.parser.XPathParser.parsePathExpression(XPathParser.java:1777)
at net.sf.saxon.expr.parser.XPathParser.parseSimpleMappingExpression(XPathParser.java:1791)
at net.sf.saxon.expr.parser.XPathParser.parseUnaryExpression(XPathParser.java:1666)
at net.sf.saxon.expr.parser.XPathParser.parseExprSingle(XPathParser.java:653)
at net.sf.saxon.expr.parser.XPathParser.parseExpression(XPathParser.java:592)
at net.sf.saxon.expr.parser.XPathParser.parse(XPathParser.java:464)
at net.sf.saxon.expr.parser.ExpressionTool.make(ExpressionTool.java:98)
at net.sf.saxon.sxpath.XPathEvaluator.createExpression(XPathEvaluator.java:144)
at net.sf.saxon.s9api.XPathCompiler.internalCompile(XPathCompiler.java:506)
at net.sf.saxon.s9api.XPathCompiler.compile(XPathCompiler.java:481)
at xslt.XSLT.main(XSLT.java:35)
如果我尝试通过 XPathExecutable viewPath = xpath.compile(path); 编译 xPath,则会出现此错误。
【问题讨论】:
-
鉴于您似乎正在从源代码自己构建撒克逊版本,并给出错误消息(“无法实例化...”),我怀疑存在构建问题。可能有一个 net.sf.saxon.expr.SystemFunctionCall 需要的类,您已将其排除在构建之外。使用类加载器跟踪运行可能有助于诊断它。
-
我在标准 java 应用程序中运行相关的 code-sn-p 并获得了堆栈跟踪,您可以在我的编辑帖子中找到它。