问题

def avoid_xml_output_issue():
    xml_text = """
    How do I avoid `
` in my XML output?

    JDOM talks about this in the javadoc of the method [Format.setLineSeparator][1].

    For the sake of this question, please assume that I only get an XML document that I have to serialize. XML element texts might contain any combination of \\r, \\n and \\r\\n, from a database, UI component, browser, program, etc.

    Is it possible to configure JDOM to only write \\r\\n, and never `
`?

    Is this a specialty of JDOM or do other XML libraries behave the same? Will have to check...

    The only idea I have so far is to iterate the complete document and remove any occurence of \\r in any text property of any element. If that is indeed my only option, I would also be interested in a correct and readable way of doing so.

    Another idea I have is to clean the output: `xml.replace("
", "")`

    Example
    -------

    ```java
      public static void main(String[] args) throws Exception
      {
        JTextPane pane = new JTextPane();
        pane.setText("line 1\\r\\nline 2");
        //    pane.setText("line 1\\nline 2");
        Element element = new Element("el");
        element.setText(pane.getText());

        Format format = Format.getPrettyFormat();
        format.setLineSeparator("\\r\\n");
        StringWriter writer = new StringWriter();
        new XMLOutputter(format).output(new Document(element), writer);
        System.out.println(writer.toString());
      }
    ```

    Output
    ------

    ```xml
        <?xml version="1.0" encoding="UTF-8"?>
        <el>line 1
        line 2</el>
    ```

    Context
    -------

    I ran into this because JTextPane.getText() sometimes returned text with just \\n, and sometimes with \\r\\n. JTextPane also has some pretty crazy end of line logic. See [DefaultEditorKit][2] (search for `EndOfLineStringProperty`).

      [1]: http://www.jdom.org/docs/apidocs/org/jdom2/output/Format.html#setLineSeparator(java.lang.String)
      [2]: https://docs.oracle.com/javase/8/docs/api/javax/swing/text/DefaultEditorKit.html
    """
    
    return xml_text

  public static void main(String[] args) throws Exception
  {
    JTextPane pane = new JTextPane();
    pane.setText("line 1\r\nline 2");
    //    pane.setText("line 1\nline 2");
    Element element = new Element("el");
    element.setText(pane.getText());

    Format format = Format.getPrettyFormat();
    format.setLineSeparator("\r\n");
    StringWriter writer = new StringWriter();
    new XMLOutputter(format).output(new Document(element), writer);
    System.out.println(writer.toString());
  }

    <?xml version="1.0" encoding="UTF-8"?>
    <el>line 1
    line 2</el>

答案1

得分: 2

文档中引用的内容非常强调答案是“否”。

每当它在输入字符串中看到“\r”时，它都会将其替换为“
”。使用setLineSeparator只会改变“\n”被转换成什么。

如果调用：format.setLineSeparator(LineSeparator.NONE);，会发生什么情况？