在java中将文本文件转换为xml

Question

我有一个包含以下条目的文本文件

1 
244699000
52.467286666666666
4.611188333333334

我想将其转换为XML文件，如下所示

<?xml version="1.0" encoding="ISO-8859-1"?>
<SYSTEM-TRACKS> 
<AIS-SENSOR ID ="1">
    <MMSI>244699000 </MMSI>
    <LATITUDE> 52.467286666666666 </LATITUDE>
    <LONGITUDE> 4.611188333333334 </LONGITUDE>  
</AIS-SENSOR> 
</SYSTEM-TRACKS>

以下是我找到的代码

public class ToXML {

BufferedReader in;
StreamResult out;

TransformerHandler th;
AttributesImpl atts;

public static void main(String args[]) {
    new ToXML().doit();
}

public void doit() {
    try {
        in = new BufferedReader(new FileReader("data"));
        out = new StreamResult("data.xml");
        initXML();
        String str;

        while ((str = in.readLine()) != null) {

            process(str);

        }
        in.close();
        closeXML();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public void initXML() throws ParserConfigurationException,
        TransformerConfigurationException, SAXException {
    // JAXP + SAX
    SAXTransformerFactory tf = (SAXTransformerFactory) SAXTransformerFactory
            .newInstance();

    th = tf.newTransformerHandler();
    Transformer serializer = th.getTransformer();
    serializer.setOutputProperty(OutputKeys.ENCODING, "ISO-8859-1");
    // pretty XML output
    serializer.setOutputProperty(
            "{http://xml.apache.org/xslt}indent-amount", "4");
    serializer.setOutputProperty(OutputKeys.INDENT, "yes");
    th.setResult(out);
    th.startDocument();
    atts = new AttributesImpl();
    th.startElement("", "", "SYSTEM-TRACKS", atts);

}

public void process(String s) throws SAXException {
    String elements[] = s.split("\\r?\\n");
    atts.clear();

    th.startElement("", "", "AIS-SENSOR", atts);
    th.characters(elements[0].toCharArray(), 0, elements[0].length());

    th.startElement("", "", "MMSI", atts);
    th.characters(elements[1].toCharArray(), 0, elements[1].length());
    th.endElement("", "", "MMSI");

    th.startElement("", "", "LATITUDE", atts);
    th.characters(elements[2].toCharArray(), 0, elements[2].length());
    th.endElement("", "", "LATITUDE");

    th.startElement("", "", "LONGITUDE", atts);
    th.characters(elements[3].toCharArray(), 0, elements[3].length());
    th.endElement("", "", "LONGITUDE");

}

public void closeXML() throws SAXException {
    th.endElement("", "", "AIS-SENSOR");
    th.endElement("", "", "SYSTEM-TRACKS");
    th.endDocument();
}

}

但是当我执行它时会出现以下错误

java.lang.ArrayIndexOutOfBoundsException: 1
at ToXML.process(ToXML.java:76)
at ToXML.doit(ToXML.java:38)
at ToXML.main(ToXML.java:26)

任何人都可以帮我制作一个如上所示的正确XML文件吗？

提前致谢

Answer 1

使用DOM：

DocumentBuilderFactory f = DocumentBuilderFactory.newInstance();
DocumentBuilder b = f.newDocumentBuilder();
DOMImplementation i = b.getDOMImplementation();
Document d = i.createDocument( null , null , null );

然后，只需构建它添加节点：

d.appendChild( d.createElement( ... ) ... );

Answer 2

您只需从文件中的一行调用流程，然后尝试按新行拆分。你的数组的长度可能是1。

String tmp = "";
while ((str = in.readLine()) != null) 
{
    tmp += str;
}
process(tmp);

试试这个。

Answer 3

你的方法很奇怪。您是逐行阅读，然后按换行拆分行，但每行只有一个值，因此您的拆分只返回一个条目。我建议采用这种方法：

    String str;
    int counter = -1;
    while ((str = in.readLine()) != null) {
        counter++;
        if(counter % 4 == 0) {
            process1(str); // add AIS-SENSOR element
            continue;
        }
        if(counter % 4 == 1) {
            process2(str); // add MMSI element
            continue;
        }
        if(counter % 4 == 2) {
            process3(str); // add LATITUDE element
            continue;
        }
        if(counter % 4 == 3) {
            process4(str); // add LONGITUDE element and close AIS-SENSOR
            continue;
        }          
    }

counter会跟踪文件中的当前行。 process1中的每一个都将根据相应行上的值添加不同的元素。

Answer 4

首先在doit（）中读取你文件中的一行（这意味着你的第一个换行符号） 然后你要在线条上拆分读取线。

因此拆分将始终给出一个长度为1的数组，这会导致在使用索引1（数组中的第二个元素）时发出异常。

你的txt文件应该包含1行所有4行，或者你应该重写代码来处理txt文件。

Answer 5

将您的文本文件读取为XML，如下所示：

void readXML(){
    File textFile=...
    Scanner scanner= new Scanner(textFile);
    ContentHandler xmlContentHandler xml=...
   //make sure to startDocument() with xmlContentHandler 

    while (scanner.hasNext()){
        addStartNodeWithAttribute("AIS-SENSORD", scanner.next());

        //move these to a method and use a for loop i=0..<3
        xmlContentHandler.startElement("","","MMSI",new AttributesImpl());
        String mmsi=scanner.next();
        contenthandler.characters(mmsi.toCharArray(), 0, mmsi.length());
        contenthandler.endElement("","","MMSI");

        xmlContentHandler.startElement("","","LATITUDE",new AttributesImpl());
        String lat=scanner.next();
        contenthandler.characters(lat.toCharArray(), 0, lat.length());
        contenthandler.endElement("","","LATITUDE");

        xmlContentHandler.startElement("","","LONGITUDE",new AttributesImpl());
        String long=scanner.next();
        contenthandler.characters(long.toCharArray(), 0, long.length());
        contenthandler.endElement("","","LONGITUDE");
    }

    //make sure to endDocument() with xmlContentHandler
}

Answer 6

// This is the original coding with the necessary changes to make it work.
// 1. Out destination is a FileWriter
// 2. Read the 4 lines into an array.
// 3. Process the array.
//      patrice_cotte@hotmail.com
package com.my.package;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.sax.SAXTransformerFactory;
import javax.xml.transform.sax.TransformerHandler;
import javax.xml.transform.stream.StreamResult;

import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;

/* 
 * This program reads a 4 lines text file land creates an XML structure around
 * the raw data. The XML structure is then copied to an xml output file. 
 */
public class Txt2XML {

    BufferedReader in;
    StreamResult out;

    TransformerHandler th;
    AttributesImpl atts;

    // Here's our entry point ... 
    public static void main(String args[]) {
        new Txt2XML().doit();
    }

    public void doit() {
        try {
            in = new BufferedReader(new FileReader("conf/testdata.txt"));
            out = new StreamResult(new FileWriter("conf/testdata.xml"));
            initXML();
            String str;
            // declare an array that can contain 4 strings
            String[] SArray=new String[4];
            int i = 0;

            while ((str = in.readLine()) != null) {
//              System.out.println("input line: " + str);
                SArray[i]=str;
                i++;

            }

            process(SArray);

            in.close();
            closeXML();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void initXML() throws ParserConfigurationException,
            TransformerConfigurationException, SAXException {
        // JAXP + SAX
        SAXTransformerFactory tf = (SAXTransformerFactory) SAXTransformerFactory
                .newInstance();

        th = tf.newTransformerHandler();
        Transformer serializer = th.getTransformer();
        serializer.setOutputProperty(OutputKeys.ENCODING, "ISO-8859-1");
        // pretty XML output
        serializer.setOutputProperty(
                "{http://xml.apache.org/xslt}indent-amount", "4");
        serializer.setOutputProperty(OutputKeys.INDENT, "yes");
        th.setResult(out);
        th.startDocument();
        atts = new AttributesImpl();
        th.startElement("", "", "SYSTEM-TRACKS", atts);

    }

    public void process(String[] elements) throws SAXException {
//      System.out.println("number of elements: " + elements.length);
        atts.clear();

        th.startElement("", "", "AIS-SENSOR", atts);
        th.characters(elements[0].toCharArray(), 0, elements[0].length());

        th.startElement("", "", "MMSI", atts);
        th.characters(elements[1].toCharArray(), 0, elements[1].length());
        th.endElement("", "", "MMSI");

        th.startElement("", "", "LATITUDE", atts);
        th.characters(elements[2].toCharArray(), 0, elements[2].length());
        th.endElement("", "", "LATITUDE");

        th.startElement("", "", "LONGITUDE", atts);
        th.characters(elements[3].toCharArray(), 0, elements[3].length());
        th.endElement("", "", "LONGITUDE");

    }

    public void closeXML() throws SAXException {
        th.endElement("", "", "AIS-SENSOR");
        th.endElement("", "", "SYSTEM-TRACKS");
        th.endDocument();
    }
}