Question

我想从文件夹中读取xml文件，我想更新它并制作新的流文件（我的代码将放在nifi处理器中），这将包含这些更新的数据，我得到了例外lilke这个：

引起：javax.script.ScriptException：javax.script.ScriptException：org.xml.sax.SAXParseException; lineNumber：1; columnNumber：1; prolog中不允许使用内容。

在 org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval（GroovyScriptEngineImpl.java:159）在 javax.script.AbstractScriptEngine.eval（AbstractScriptEngine.java:264）在 org.apache.nifi.script.impl.GroovyScriptEngineConfigurator.eval（GroovyScriptEngineConfigurator.java:54）在 org.apache.nifi.processors.script.ExecuteScript.onTrigger（ExecuteScript.java:220） ...省略了11个常见帧引起的：javax.script.ScriptException： org.xml.sax.SAXParseException; lineNumber：1; columnNumber：1;内容不允许在prolog中。在 org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval（GroovyScriptEngineImpl.java:355）在 org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval（GroovyScriptEngineImpl.java:153） ...省略了14个常见帧引起的： org.xml.sax.SAXParseException：prolog中不允许使用内容。在 com.sun.org.apache.xerces.internal.parsers.DOMParser.parse（DOMParser.java:257）在 com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse（DocumentBuilderImpl.java:339）在javax.xml.parsers.DocumentBuilder.parse（DocumentBuilder.java:121）在javax.xml.parsers.DocumentBuilder $ parse.call（未知来源）at Script13.run（Script13.groovy：54）at org.codehaus.groovy.jsr223.GroovyScriptEngineImpl.eval（GroovyScriptEngineImpl.java:352） ...省略了15个常见帧

1. 我应该更改什么？（除了使用doc = builder.parse（file）更改doc = builder.parse（inputStream），因为我需要使用字符串数据进行后续处理）

我无法完成任务的另一个原因是我无法生成我将放置所有更新的xml数据的流文件，由于某种原因我得到了空的流文件，即使我使用此doc = builder.parse（file）我的意思是使用配置文件phisically（文件文件=新文件（＆＃39;路径＆＃39;）），我应该改变什么来改善这种情况。
如果我使用字符串内容，我应该使用任何替代方法来获取xml标记数据，除了使用NodeList（我的意思是可以使用任何更好的用例）？这是我的常规代码：

import org.apache.commons.io.IOUtils;
import java.nio.charset.StandardCharsets;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.w3c.dom.Node;
import org.w3c.dom.Element;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.nio.channels.Channels;
import java.nio.channels.FileLock;
import javax.xml.xpath.*;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;

  File file = new File("C://Users//user//Desktop//2//conf.xml");
        String content = '';




        RandomAccessFile ini = new RandomAccessFile(file, "rws");
        FileLock lock = ini.getChannel().lock();
        BufferedReader s;
        DocumentBuilder dBuilder = null;
        Document doc=null;
        String start,startDate,endDate,runAs,makeVersion,patch;
        try {
            String sCurrentLine;
            s= new BufferedReader(Channels.newReader(ini.getChannel(), "UTF-8"));


            while ((sCurrentLine = s.readLine()) != null) {
                content+=sCurrentLine;
            }

            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();
            InputStream inputStream = new    ByteArrayInputStream(content.getBytes());
            doc = builder.parse(inputStream);
            NodeList nList = doc.getElementsByTagName("localAttributes");
            for (int temp = 0; temp < nList.getLength(); temp++) {

                Node nNode = nList.item(temp);


                if (nNode.getNodeType() == Node.ELEMENT_NODE) {

                    Element eElement = (Element) nNode;


                    start = eElement.getElementsByTagName("start").item(0).getTextContent();
                    startDate = eElement.getElementsByTagName("startDate").item(0).getTextContent();
                    endDate = eElement.getElementsByTagName("endDate").item(0).getTextContent();
                    patch = eElement.getElementsByTagName("patch").item(0).getTextContent();
                    runAs = eElement.getElementsByTagName("runAs").item(0).getTextContent();
                    makeVersion = eElement.getElementsByTagName("makeVersion").item(0).getTextContent();

                }
            }
          def flowFile1=session.create();
            flowFile1 = session.putAttribute(flowFile1, "start", start);
            flowFile1 = session.putAttribute(flowFile1, "startDate", startDate);
            flowFile1 = session.putAttribute(flowFile1, "endDate", endDate);
            flowFile1 = session.putAttribute(flowFile1, "runAs", runAs);
            flowFile1 = session.putAttribute(flowFile1, "patch", patch);
            flowFile1 = session.putAttribute(flowFile1, "makeVersion", makeVersion);

            flowFile1 = session.putAttribute(flowFile1, "filename", "conf.xml");

            Document xmlDocument = builder.parse(inputStream);


            XPathExpression myNodeList = (XPathExpression) xPath.compile("/localAttributes");
            Node nodeGettingChanged = (Node) myNodeList.evaluate(xmlDocument, XPathConstants.NODE);
            NodeList childNodes = nodeGettingChanged.getChildNodes();
            for (int i = 0; i != childNodes.getLength(); ++i) {
                Node child = childNodes.item(i);
                if (!(child instanceof Element))
                    continue;

                if (child.getNodeName().equals("runAs"))
                    child.getFirstChild().setNodeValue("false");

            }


            session.write(flowFile1, new StreamCallback() {
                @Override
                public void process(InputStream inputStream1, OutputStream outputStream) throws IOException {
                    TransformerFactory transformerFactory = TransformerFactory.newInstance();

                    try {
                        transformer = transformerFactory.newTransformer();
                    } catch (TransformerConfigurationException e) {
                        e.printStackTrace();
                    }
                   DOMSource source1 = new DOMSource(xmlDocument);

                    ByteArrayOutputStream bos = new ByteArrayOutputStream();
                    StreamResult result = new StreamResult(bos);


                    try {
                        transformer.transform(source1, result);
                    } catch (TransformerException e) {
                        e.printStackTrace();
                    }
                    byte[] array = bos.toByteArray();
                    outputStream.write(array);
                }

            });


        session.transfer(flowFile1,REL_SUCCESS);



        } finally {
            lock.release();
            s.close();
            ini.close();
        }

        try {
            FileInputStream input = new FileInputStream(file);


        } catch (FileNotFoundException e) {
            Thread.sleep(5000);


        } catch (Exception e) {
            e.printStackTrace();
        }

Groovy：如何将文本响应解析为xml Document

0 个答案: