我想将输出流转换为String对象

Question

I want to convert an OutputStream into a String object. I am having an OutputStream object returned after marshalling the JAXB object.

Answer 1

not very familiar with jaxb, from what i was able to find you can convert into a string using

public String asString(JAXBContext pContext, 
                        Object pObject)
                            throws 
                                JAXBException {

    java.io.StringWriter sw = new StringWriter();

    Marshaller marshaller = pContext.createMarshaller();
    marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8");
    marshaller.marshal(pObject, sw);

    return sw.toString();
}

ws.apache.org

but I'm not sure about a stirng object. still searching.

** EDIT

Marshalling a non-element

Another common use case is where you have an object that doesn't have @XmlRootElement on it. JAXB allows you to marshal it like this:

marshaller.marshal( new JAXBElement(
new QName("","rootTag"),Point.class,new Point(...)));

This puts the element as the root element, followed by the contents of the object, then . You can actually use it with a class that has @XmlRootElement, and that simply renames the root element name.

At the first glance the second Point.class parameter may look redundant, but it's actually necessary to determine if the marshaller will produce (infamous) @xsi:type. In this example, both the class and the instance are Point, so you won't see @xsi:type. But if they are different, you'll see it.

This can be also used to marshal a simple object, like String or an integer.

marshaller.marshal( new JAXBElement(
new QName("","rootTag"),String.class,"foo bar"));

But unfortunately it cannot be used to marshal objects like List or Map, as they aren't handled as the first-class citizen in the JAXB world.

found HERE

Answer 2

    StringWriter sw = new StringWriter();
    com.integra.xml.Integracao integracao = new Integracao();
    integracao.add(...);
try {
    JAXBContext context = JAXBContext.newInstance("com.integra.xml");
    Marshaller marshaller = context.createMarshaller();
    marshaller.marshal(integracao, sw );
    System.out.println(sw.toString());
} catch (JAXBException e) {
    e.printStackTrace();
}

Answer 3

public String readFile(String pathname) throws IOException {
    File file = new File(pathname);
    StringBuilder fileContents = new StringBuilder((int) file.length());
    Scanner scanner = new Scanner(file);
    String lineSeparator = System.getProperty("line.separator");

    try {
        while (scanner.hasNextLine()) {
            fileContents.append(scanner.nextLine() + lineSeparator);
        }
        return fileContents.toString();
    }
    finally {
        scanner.close();
    }
}    

Method to handle the XML and convert it to a string.

JAXBContext jc = JAXBContext.newInstance(ClassMatchingStartofXMLTags.class);
    Unmarshaller unmarshaller = jc.createUnmarshaller();
    //store filepath to be used
    String filePath = "YourXMLFile.xml";
    File xmlFile = new File(filePath);
    //Set up xml Marshaller
    ClassMatchingStartofXMLTags xmlMarshaller = (ClassMatchingStartofXMLTags) unmarshaller.unmarshal(xmlFileEdit);
    Marshaller marshaller = jc.createMarshaller();
    marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
    // Use marshall to output the contents of the xml file
    System.out.println("Marshalled XML\n");
    marshaller.marshal(xmlMarshaller, System.out); 
    //Use Readfile method to convert the XML to a string and output the results
    System.out.println("\nXML to String");
    String strFile = ReadFile(xmlFile)
    System.out.println(strFile);     

Method within your class to get the XML and Marshall it Edit The above method will both output the marshalled xml and also the xml as a string.

Answer 4

Yes, there is a way to do it: just pass the String writer as input to it. So that it the xml created will be written to it

   public void saveSettings() throws IOException {
       FileOutputStream os = null;
       //Declare a StringWriter to which the output has to go
       StringWriter sw = new StringWriter();
       try {
           Answer ans1=new Answer(101,"java is a programming language","ravi");  
           Answer ans2=new Answer(102,"java is a platform","john");  

           ArrayList<Answer> list=new ArrayList<Answer>();  
           list.add(ans1);  
           list.add(ans2);  

           settings=new Question(1,"What is java?",list); 
           os = new FileOutputStream(FILE_NAME);
           this.marshaller.marshal(settings, new StreamResult(sw));
           System.out.println(sw.toString());
           new File(FILE_NAME).delete();
       } finally {
           if (os != null) {
               os.close();
           }
       }
   }