我使用StAx编写了一个XML解析器,用于解析从服务器接收的XML流。这是我的代码:
private Map<String, IUnitaryAction> parse(InputStream is) throws XMLStreamException {
XMLInputFactory factory = XMLInputFactory.newInstance();
XMLStreamReader reader = factory.createXMLStreamReader(is);
boolean action = false;
Map<String, IUnitaryAction> actionsMap = new HashMap<String, IUnitaryAction>();
while(reader.hasNext()){
int type = reader.next();
switch(type){
case XMLStreamReader.START_ELEMENT :
action = reader.getLocalName().equals("action-description");
break;
case XMLStreamReader.CHARACTERS :
if( action ){
String act = reader.getText();
System.out.println("Action trouvées " + act);
String[] praxiscmd = act.split("_");
if("CREATE".equals(praxiscmd[0])){
Create c = new Create(praxiscmd[1], praxiscmd[2], null);
actionsMap.put(praxiscmd[1], c);
} else if("DELETE".equals(praxiscmd[0])){
Delete d = new Delete(praxiscmd[1],praxiscmd[2], null);
actionsMap.put(praxiscmd[1], d);
} else if ("ADDPROPERTY".equals(praxiscmd[0])) {
AddProperty ap = new AddProperty(praxiscmd[1],
praxiscmd[2], praxiscmd[3], null);
actionsMap.put(praxiscmd[1], ap);
} else if ("ADDREFERENCE".equals(praxiscmd[0])) {
AddReference ar = new AddReference(praxiscmd[1],
praxiscmd[2], praxiscmd[3], null);
actionsMap.put(praxiscmd[1], ar);
} else if ("REMPROPERTY".equals(praxiscmd[0])) {
RemProperty rp = new RemProperty(praxiscmd[1],
praxiscmd[2], praxiscmd[3], null);
actionsMap.put(praxiscmd[1], rp);
} else if ("REMREFERENCE".equals(praxiscmd[0])) {
RemReference rr = new RemReference(praxiscmd[1],
praxiscmd[2], praxiscmd[3], null);
actionsMap.put(praxiscmd[1], rr);
}
}
}
}
我在这一行代码中遇到了错误:int type = reader.next()
javax.xml.stream.XMLStreamException: ParseError at [row,col]:[1,1]
Message: Premature end of file.
at com.sun.org.apache.xerces.internal.impl.XMLStreamReaderImpl.next(XMLStreamReaderImpl.java:584)
at fr.lip6.graphelex.TelexImpl.parse(TelexImpl.java:147)
at fr.lip6.graphelex.TelexImpl.sendHttpRequest(TelexImpl.java:264)
at fr.lip6.graphelex.TelexImpl.schedules(TelexImpl.java:116)
at fr.lip6.graphelex.MapperImpl.send(MapperImpl.java:92)
at fr.lip6.graphelex.GraphElexAgent.executeCycle(GraphElexAgent.java:81)
at praxis.guidance.agent.Agent.run(Agent.java:71)
at java.lang.Thread.run(Thread.java:636)
我不明白问题出在哪里,因为我在另一个案例中使用了相同的解析器,它完美地工作了。以下是我从服务器接收到的 XML 流的示例: <?xml version="1.0" encoding="UTF-8" standalone="no"?>
<responses>
<executed-commands>
<command><name>GETLASTSCEDULES</name>
<status-code>200</status-code>
<description>last schedule returned</description>
</command>
</executed-commands>
<schedules><schedule><schedule-id>0</schedule-id>
<doc-id>/telexDocuments/doc.dox</doc-id>
<actions>
<action>
<action-description>CREATE__8VtAMXv4EeCwaM2v2VqUyg_Model</action-description>
<action-id>/telexDocuments/doc.dox:Peer#server2:hephaistos:0:15</action-id>
</action>
</actions>
<non-actions/></schedule></schedules>
<get-constraints/>
</responses>
能否给一些建议?
编辑:我可能已经找到了答案。问题出在我从服务器接收InputStream作为答案,然后进行读取解析。你可能知道,在Java中,一旦InputStream被读取解析,它会自动关闭。有时候我们会忘记这点。感谢文档