How to remove extra empty lines from XML file?

Question

In short; i have many empty lines generated in an XML file, and i am looking for a way to remove them as a way of leaning the file. How can i do that ?

For detailed

Answer 1

When i used dom4j to remove some elements and i met the same question,the solution above not useful without adding some other required jars.Finally,i find out a simple solution only need to use JDK io pakage:

1. use BufferedReader to read the xml file.

StringBuilder stringBuilder = new StringBuilder();
FileInputStream fis = new FileInputStream(outFile);
InputStreamReader isr = new InputStreamReader(fis);
BufferedReader br = new BufferedReader(isr);
String s;
while ((s = br.readLine()) != null) {
  if (s.trim().length() > 0) {
    stringBuilder.append(s).append("\n");
  }
}

2. write the string to the xml file

OutputStreamWriter osw = new OutputStreamWriter(fou);
BufferedWriter bw = new BufferedWriter(osw);
String str = stringBuilder.toString();
bw.write(str);
bw.flush();

3. remember to close all the stream