使用Java将两个XML文件合并到一个XML文件中

Question

我一直坚持如何组合两个不同的XML文件（它具有相同的结构）。当我对它做一些研究时，人们会说必须使用像DOM或StAX这样的XML解析器。但不能与常规的IOStream一起使用？我目前正在尝试使用IOStream的帮助，但这不能解决我的目的，它更复杂。

例如，我试过的是;

   public class GUI { 

      public static void main(String[] args) throws Exception { 

      // Creates file to write to 
      Writer output = null; 
      output = new BufferedWriter(new FileWriter("C:\\merged.xml")); 
      String newline = System.getProperty("line.separator"); 

      output.write(""); 

      // Read in xml file 1 
      FileInputStream in = new FileInputStream("C:\\1.xml"); 
      BufferedReader br = new BufferedReader(new InputStreamReader(in)); 
      String strLine; 

      while ((strLine = br.readLine()) != null) { 

      if (strLine.contains("<MemoryDump>")){ 
      strLine = strLine.replace("<MemoryDump>", "xmlns:xsi"); 
      } 
      if (strLine.contains("</MemoryDump>")){ 
      strLine = strLine.replace("</MemoryDump>", "xmlns:xsd"); 
      } 

      output.write(newline); 
      output.write(strLine); 

      System.out.println(strLine); 
      } 

      // Read in xml file 2 
      FileInputStream in = new FileInputStream("C:\\2.xml"); 
      BufferedReader br1 = new BufferedReader(new InputStreamReader(in)); 
      String strLine1; 

      while ((strLine1 = br1.readLine()) != null) { 

      if (strLine1.contains("<MemoryDump>")){ 
      strLine1 = strLine1.replace("<MemoryDump>", ""); 
      } 
      if (strLine1.contains("</MemoryDump>")){ 
      strLine1 = strLine1.replace("</MemoryDump>", ""); 
      } 

      output.write(newline); 
      output.write(strLine1); 

我请求您请让我知道如何通过添加其他内容来合并两个XML文件。如果你可以提供一些示例链接，那将是非常棒的！！

谢谢您提前..！ System.out.println（strLine1）; }

}

Answer 1

不完全相信你希望做什么。合并是否意味着：

a。您想要合并2个DOM的内容，并创建一个对象模型（一个有效的模型），并附加节点

b。你想合并这两个文件一个接一个，而不关心实际内容

如果它是一个，使用XML解析器。当然，你可以手动编写这些东西，并尝试将流处理成dom对象，但是你会重写很多这些解析器的用途。为什么要重写那些已经存在的东西。

如果是b，只是做一个愚蠢的副本。复制第一个文件（再次使用实用程序，例如apache常用的FileUtil允许您复制文件。除非必要，否则不要写入），打开一个IO流到复制的文件，然后读取和写入第二个文件。

Answer 2

作为一般规则，绝对不要在词法级别对XML进行任何处理：始终使用XML解析器。 （如果（a）您是一位XML专家，那么您可以打破此规则，因此您知道可能出错的地方，以及（b）您知道结果始终不必是正确的。）

其次，进行这种处理最简单的方法是使用为该作业设计的语言，如XSLT或XQuery。使用Java使它非常花费工作。

如果您对要合并的文件类型更具体，以及希望输出结果如何，我们可以给出更准确的答案。

Answer 3

package com.cts.sterling.order; 

//package com.academy.ecommerce.sterling.userexits; 
import java.io.File; 
import javax.xml.parsers.DocumentBuilder; 
import javax.xml.parsers.DocumentBuilderFactory; 
import org.w3c.dom.Document; 
import org.w3c.dom.Element; 
import org.w3c.dom.NodeList; 
import com.cts.sterling.custom.accelerators.util.XMLUtil; 


public class MergeXml { 

    public static Document mergeXml(Document doc1, Document doc2) 

      throws Exception { 

     // Getting the attributes of OrderLine from document2 and document1 
     NodeList objOrderLineList2 = doc2.getElementsByTagName("OrderLine"); 
     NodeList objOrderLineList1 = doc1.getElementsByTagName("OrderLine"); 

     // Creating Element for OrderLine 
     Element eleOrderline2 = (Element) objOrderLineList2.item(0); 
     Element eleOrderline1 = (Element) objOrderLineList1.item(0); 

     // Declaring attributes as String array 
     String[] Line1={"LineType","LevelOfService"}; 

     // Copying attributes from document2 to document1 
     XMLUtil.copyAttributes(eleOrderline2, eleOrderline1, Line1); 

     // Getting the attributes of Extn from document2 and document1 
     NodeList objExtn2 = doc2.getElementsByTagName("Extn"); 
     NodeList objExtn1 =doc1.getElementsByTagName("Extn"); 

     // Creating Element for Extn 
     Element eleExtn2 = (Element) objExtn2.item(0); 
     Element eleExtn1 = (Element) objExtn1.item(0); 

     // Declaring attributes as String array 
     String[] Line2={"ExtnMediaCode","ExtnLastName","ExtnGroupID"}; 

     // Copying attributes from document2 to document1 
     XMLUtil.copyAttributes(eleExtn2, eleExtn1, Line2); 

     // Getting the attributes of WSIAddnlOrderLineData from document2 and document1 
     NodeList objAddln2 = doc2.getElementsByTagName("WSIAddnlOrderLineData"); 
     NodeList objAddln1 =doc1.getElementsByTagName("WSIAddnlOrderLineData"); 

     // Creating Element for WSIAddnlOrderLineData 
     Element eleAddln2 = (Element) objAddln2.item(0); 
     Element eleAddln1 = (Element) objAddln1.item(0); 

     // Declaring attributes as String array 
     String[] Line3 ={"ExtnShipMode" , "ExtnDeliverTogether","ExtnComponentReplacementIndicator","ExtnGiftCardRequiredIndicator","ExtnReplOriginalItemID", 
       "ExtnSpecialHandlingIndicator","ExtnSpecialHandlingReasonCode","ExtnCardType","ExtnCardClass","ExtnEcomSuborderNo","ExtnEcomOrderLineNo", 
       "ExtnPFSFlag","ExtnSVCCarrierServiceCode","ExtnSVCSCAC","ExtnSVCUpgradeFlag","ExtnSVCSKUType","ExtnSVCTo","ExtnSVCFrom"}; 

     // Copying attributes from document2 to document1 
     XMLUtil.copyAttributes(eleAddln2, eleAddln1, Line3); 

     // Getting the attributes of Instruction from document2 and document1 
     NodeList objInst2 = doc2.getElementsByTagName("Instruction"); 
     NodeList objInst1 =doc1.getElementsByTagName("Instruction"); 

     // Creating Element for Instruction 
     Element eleInst2 = (Element) objInst2.item(0); 
     Element eleInst1 = (Element) objInst1.item(0); 

     // Declaring attributes as String array 
     String[] Line4 ={"InstructionText","InstructionType","SequenceNo","InstructionURL","InstructionUsage"}; 

     // Copying attributes from document2 to document1 
     XMLUtil.copyAttributes(eleInst2, eleInst1, Line4); 

     //Printing output document 
     System.out.println(XMLUtil.getString(doc1)); 
     return doc1; 

    } 
    //Main method 
    public static void main(String[] args) { 
     try{ 

      File file1 = new File("D:/Handson/merge1.xml"); 
      DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance(); 
      DocumentBuilder dBuilder = dbFactory.newDocumentBuilder(); 
      Document doc1 = dBuilder.parse(file1); 
      File file2 = new File("D:/Handson/merge2.xml"); 
      Document doc2 = dBuilder.parse(file2); 

      //calling the method 
      mergeXml(doc1,doc2); 
     } 
     catch (Exception e) { 
      e.printStackTrace(); 
     } 

    } 
}