Java：如何在循環中持續更新文件

Question

我正在編寫需要不斷更新循環中的文本文件的代碼：刪除實際內容並編寫另一個文件。問題是更新沒有正確完成。它使用該文件的以前版本。

例如，在環4，所謂文件是在環3

我的問題是如何正確地更新我的文件更新的文件？

public static void main(String[] args) throws IOException { 
for(int level:levels){ 
      RecipeTree.CloneTree(root, partialroot); 
      for(int i =0; i<100; i++){ 
       RecipeTree.removalcondition = RecipeTree.levelOfConditions(depth, length, recipe, level); 
       System.out.println(removalcondition); 
       RecipeTree.PartialTree(partialroot, RecipeTree.removalcondition); 
       // Here the update of the file 
       InitSTRIPSPlanner(partialroot); 
       for(RecipeTree leaf: partialroot.getLeaves()){ 
        ........... 
       }  
      } 
     } 
public static void InitSTRIPSPlanner(RecipeTree root) throws IOException{ 
     String adresseBut = System.getProperty("user.dir") + "/prolog/test-2p/Domain_knowledge.pl"; 
     String adresseSource = System.getProperty("user.dir") + "/prolog/test-2p/STRIPS_planner.pl"; 
     try { 
      copyFileUsingStream(new File(adresseSource), new File(adresseBut)); 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 
     File fw = new File (adresseBut); 
     OutputStream output = new FileOutputStream(fw,true); 
     output.write("\n".getBytes()); 
     output.flush(); 
     FromTreeToProlog(root,output); 
     output.close(); 
    } 

    public static void FromTreeToProlog(RecipeTree root, OutputStream output) throws IOException{ 
     for(RecipeTree leaf: root.getLeaves()){ 
      if (leaf.getHead().getPostconditions() != null) { 
       output.write("\n".getBytes()); 
       output.flush(); 
       output.write("\n".getBytes()); 
       output.flush(); 
       if (leaf.getHead().getPreconditions() != null) { 
        output.write(("strips_preconditions(" 
          + leaf.getHead().getName().toLowerCase() + ",[" 
          + leaf.getHead().getPreconditions().toLowerCase()+ "]).").getBytes()); 
        output.write("\n".getBytes()); 
        output.flush(); 
       } 
       else { 
        output.write(("strips_preconditions(" 
          + leaf.getHead().getName().toLowerCase() + ",[_]).").getBytes()); 
        output.write("\n".getBytes()); 
        output.flush(); 
       } 

       output.write(("strips_achieves(" 
         + leaf.getHead().getName().toLowerCase() + "," 
         + leaf.getHead().getPostconditions().toLowerCase() 
         + ").").getBytes()); 
      } 
     } 
     for (String i : conditions) { 
      output.write(("strips_primitive(" + i.toLowerCase() + ").").getBytes()); 
      output.write("\n".getBytes()); 
      output.flush(); 
     } 
     for (String recipe : RecipeTree.RecipeCondition) { 
      output.write(("strips_preconditions(" + recipe.toLowerCase() + ",[_]).").getBytes()); 
      output.write("\n".getBytes()); 
      output.flush(); 
      output.write(("strips_achieves(" + recipe.toLowerCase() + ",c" 
        + recipe.toLowerCase() + ").").getBytes()); 
      output.write("\n".getBytes()); 
      output.flush(); 
      output.write(("strips_primitive(c" + recipe.toLowerCase() + ").").getBytes()); 
      output.write("\n".getBytes()); 
      output.flush(); 
     } 
    } 

    private static void copyFileUsingStream(File source, File dest) throws IOException { 
     InputStream is = null; 
     OutputStream os = null; 
     try { 
      is = new FileInputStream(source); 
      os = new FileOutputStream(dest); 
      byte[] buffer = new byte[1024]; 
      int length; 
      while ((length = is.read(buffer)) > 0) { 
       os.write(buffer, 0, length); 
      } 
     } finally { 
      is.close(); 
      os.close(); 
     } 
    }   

}

Answer 1

new FileOutputStream(fw, true); 

是附加，應該是任何一個

new FileOutputStream(fw, false); 
new FileOutputStream(fw); 

，如果我理解正確。

順便說一句。

copyFileUsingStream(new File(adresseSource), new File(adresseBut)); 

可能是（因爲Java的7）：

Files.copy(Paths.get(adresseSource), Paths.get(adresseBut), 
    StandardCopyOption.REPLACE_EXISTING);