POST xml data using java

Question

I have used the following java code to POST xml data to a remote url and get the response. Here, I am using an xml file as the input. What I need is to pass the xml as a string

Answer 1

The setRequestEntity method on org.apache.commons.httpclient.methods.PostMethod has an overloaded version that accepts StringRequestEntity as argument. You should use this if you wish to pass in your data as a string (as opposed to an input stream). So your code would look something like this:

String xml = "whatever.your.xml.is.here";
PostMethod post = new PostMethod(strURL);     
try {
    StringRequestEntity requestEntity = new StringRequestEntity(xml);
    post.setRequestEntity(requestEntity);
....

Hope that helps.

Answer 2

You can convert the XML to String from this method

public String convertXMLFileToString(String fileName) 
{ 
   try{ 
       DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance(); 
       InputStream inputStream = new FileInputStream(new File(fileName)); 
       org.w3c.dom.Document doc = documentBuilderFactory.newDocumentBuilder().parse(inputStream); 
       StringWriter stw = new StringWriter(); 
       Transformer serializer = TransformerFactory.newInstance().newTransformer(); 
       serializer.transform(new DOMSource(doc), new StreamResult(stw)); 
       return stw.toString(); 
   } 
   catch (Exception e) { 
       e.printStackTrace(); 
   } 
   return null; 
}

Add you can pass this string as a parameter on PostMethod like this.

PostMethod post = new PostMethod(strURL);
post.addParamter("paramName", convertXMLFileToString(strXMLFilename ) );

The whole XML will be transmitted to the client in a queryString.

Answer 3

To get your XML file contents as a String use (add catch-block for IOException)

StringBuilder bld = new StringBuilder();
FileReader fileReader = new FileReader(input);
BufferedReader reader = new BufferedReader(fileReader);
for (String line = reader.readLine(); line != null; line = reader.readLine()) {
    bld.append(line);
}
String xml = bld.toString();

The better way is to use Java Web Services JAX-WS or Java Restful Web Services JAX-RS.