xml - 如何仅使用 Parser 实例将 XML 写入文件？

Question

这是我的 Groovy 代码:

// ...
def xml = new XmlParser().parse(fileName)
xml.each { e ->
  // some changes are being made to XML
  xml.append("test", "test me")
}
def writer = new FileWriter(newFileName)
new XmlNodePrinter(new PrintWriter(writer)).print(xml)

代码有效，但输出的 XML 有很多不必要的空格。看起来我在写入文件时做错了。

附言。感谢 Tim，它应该是这样工作的(上面示例的最后一行应替换为这三行):

def printer = new XmlNodePrinter(new PrintWriter(writer))
printer.preserveWhitespace = true
printer.print(xml)

Answer 1

如果你替换会发生什么:

def writer = new FileWriter(newFileName)
new XmlNodePrinter(new PrintWriter(writer)).print(xml)

与:

new File( newFilename ).withWriter { out ->
  printer = new XmlNodePrinter( out )
  printer.preserveWhitespace = true
  printer.print( xml )
}

-- 编辑 --

正如所指出的，感觉应该是 preserveWhitespace = false，但是如果您尝试以下测试代码:

def x = """<langs type="current">
  <language>Java</language>
  <language>Groovy</language>
  <language>JavaScript</language>
</langs>"""

def xml = new XmlParser().parseText( x )
xml.appendNode 'language', 'Ruby'

def printIt = { node, pw ->
  println "With preserveWhitespace=$pw:"
  def s = new StringWriter()
  printer = new XmlNodePrinter( new PrintWriter( s ) )
  printer.preserveWhitespace = pw
  printer.print( xml )
  println s
}

printIt xml, true
printIt xml, false

你得到输出:

With preserveWhitespace=true:
<langs type="current">
  <language>Java</language>
  <language>Groovy</language>
  <language>JavaScript</language>
  <language>Ruby</language>
</langs>

With preserveWhitespace=false:
<langs type="current">
  <language>
    Java
  </language>
  <language>
    Groovy
  </language>
  <language>
    JavaScript
  </language>
  <language>
    Ruby
  </language>
</langs>