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Serializing multiline string from JsonNode to YAML string adds double quotes and "\n"

I have a YAML string where one of the attributes looks like this:
description: |
this is my description //imagine there's a space after description
this is my description in the second line
In my Java code I read it into a JsonNode like this:
JsonNode node = new YamlMapper().readTree(yamlString);
I then do some changes to it and write it back to a string like this:
new YamlMapper().writeValueAsString(node))
The new string now looks like this:
"this is my description \nthis is my description in the second line\n"
So now in the YAML file you can see the added quotes + the new line character (\n) and everything is in one line. I expect it to return the original YAML like the one above.
This is how my YAML object mapper is configured:
new ObjectMapper(
new YAMLFactory()
.disable(YAMLGenerator.Feature.MINIMIZE_QUOTES))
.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
.setSerializationInclusion(JsonInclude.Include.NON_EMPTY);
If I remove the space after description in the original YAML, it works just fine

To serialize multiline text using jackson. Jackson introduced a new flag YAMLGenerator.Feature.LITERAL_BLOCK_STYLE since version 2.9, which can be turned on as:
new ObjectMapper(
new YAMLFactory().enable(YAMLGenerator.Feature.LITERAL_BLOCK_STYLE)
).writeValueAsString(new HashMap<String, String>(){{
put("key", "test1\ntest2\ntest3");
}});
The output won't be wrapped with quotes:
---
key: |-
test1
test2
test3
Note there is a few differences between "block scalars": |, |-, >..., you can check out at https://yaml-multiline.info/

Jackson's API is too high level to control the output in detail. You can use SnakeYAML directly (which is used by Jackson under the hood), but you need to go down to the node or event level of the API to control node style in the output.
See also: I want to load a YAML file, possibly edit the data, and then dump it again. How can I preserve formatting?
This answer shows general usage of SnakeYAML's event API to keep formatting; of course it's harder to do changes on a stream of events. You might instead want to work on the node graph, this answer has some example code showing how to load YAML to a node graph, process it, and write it back again.

Externalize XML construction from a stream of CSV in Java

I get a stream of values as CSV , based on some condition I need to generate a XML including only a set of values from the CSV. For e.g .
Input : a:value1, b:value2, c:value3, d:value4, e:value5.
if (condition1)
XML O/P = <Request><ValueOfA>value1</ValueOfA><ValueOfE>value5</ValueOfE></Request>
else if (condition2)
XML O/P = <Request><ValueOfB>value2</ValueOfB><ValueOfD>value4</ValueOfD></Request>
I want to externalize the process in a way that given a template the output XML is generated accordingly. String manipulation is the easiest way of implementing this but I do not want to mess up the XML if some special characters appear in the input, etc. Please suggest.

Perhaps you could benefit from templating engine, something like Apache Velocity.

I would suggest creating an xsd and using JAXB to create the Java binding classes that you can use to generate the XML.

I recommend my own templating engine (JATL http://code.google.com/p/jatl/) Although its geared to (X)HTML its also very good at generating XML.
I didn't bother solving the whole problem for you (that is double splitting on the input ("," and then ":").) but this is how you would use JATL.
final String a = "stuff";
HtmlWriter html = new HtmlWriter() {
#Override
protected void build() {
//If condition1
start("Request").start("ValueOfA").text(a).end().end();
}
};
//Now write.
StringWriter writer = new StringWriter();
String results = html.write(writer).getBuffer().toString();
Which would generate
<Request><ValueOfA>stuff</ValueOfA></Request>
All the correct escaping is handled for you.

How to convert any input XML file to similar Java object structure?

Hi all can any one tell me is it possible to convert any XML file file to equivalent java object using java?

You want a DOM parser. There are many around, a Google search for "Java DOM parser" will help you. Take this page for example.

You are probably looking for JAXB.

Use XStream library it is quite simple:
http://x-stream.github.io/tutorial.html
// object -> XML -> File
XStream xstream = new XStream(driver);
String data = xstream.toXML(metaData);
// XML -> object
XStream xstream = new XStream(new JettisonMappedXmlDriver());
YourClass obj = (UourClass)xstream.fromXML(jSON);

You could use unmarshall function in castor.

Let me add another to the collection.
Have a look at the Apache Jakarta Digester this is what Tomcat uses to automap XML files (like server.xml).

Converting a raw file (binary data ) into XML file

I'm working on a project under which i have to take a raw file from the server and convert it into XML file.
Is there any tool available in java which can help me to accomplish this task like JAXP can be used to parse the XML document ?

I guess you will need your objects for later use ,so create MyObject that will be some bean that you will load the values form your Raw File and you can write this to someFile.xml
FileOutputStream os = new FileOutputStream("someFile.xml");
XMLEncoder encoder = new XMLEncoder(os);
MyObject p = new MyObject();
p.setFirstName("Mite");
encoder.writeObject(p);
encoder.close();
Or you con go with TransformerFactory if you don't need the objects for latter use.

Yes. This assumes that the text in the raw file is already XML.
You start with the DocumentBuilderFactory to get a DocumentBuilder, and then you can use its parse() method to turn an input stream into a Document, which is an internal XML representation.
If the raw file contains something other than XML, you'll want to scan it somehow (your own code here) and use the stuff you find to build up from an empty Document.
I then usually use a Transformer from a TransformerFactory to convert the Document into XML text in a file, but there may be a simpler way.

JAXP can also be used to create a new, empty document:
Document dom = DocumentBuilderFactory.newInstance()
.newDocumentBuilder()
.newDocument();
Then you can use that Document to create elements, and append them as needed:
Element root = dom.createElement("root");
dom.appendChild(root);
But, as Jørn noted in a comment to your question, it all depends on what you want to do with this "raw" file: how should it be turned into XML. And only you know that.

I think if you try to load it in an XmlDocument this will be fine

Creating xml from with java

I need your expertise once again. I have a java class that searches a directory for xml files (displays the files it finds in the eclipse console window), applies the specified xslt to these and sends the output to a directory.
What I want to do now is create an xml containing the file names and file format types. The format should be something like;
<file>
<fileName> </fileName>
<fileType> </fileType>
</file>
<file>
<fileName> </fileName>
<fileType> </fileType>
</file>
Where for every file it finds in the directory it creates a new <file>.
Any help is truely appreciated.

Use an XML library. There are plenty around, and the third party ones are almost all easier to use than the built-in DOM API in Java. Last time I used it, JDom was pretty good. (I haven't had to do much XML recently.)
Something like:
Element rootElement = new Element("root"); // You didn't show what this should be
Document document = new Document(rootElement);
for (Whatever file : files)
{
Element fileElement = new Element("file");
fileElement.addContent(new Element("fileName").addContent(file.getName());
fileElement.addContent(new Element("fileType").addContent(file.getType());
}
String xml = XMLOutputter.outputString(document);

Have a look at DOM and ECS. The following example was adapted to you requirements from here:
XMLDocument document = new XMLDocument();
for (File f : files) {
document.addElement( new XML("file")
.addXMLAttribute("fileName", file.getName())
.addXMLAttribute("fileType", file.getType())
)
);
}

You can use the StringBuilder approach suggested by Vinze, but one caveat is that you will need to make sure your filenames contain no special XML characters, and escape them if they do (for example replace < with <, and deal with quotes appropriately).
In this case it probably doesn't arise and you will get away without it, however if you ever port this code to reuse in another case, you may be bitten by this. So you might want to look at an XMLWriter class which will do all the escaping work for you.

Well just use a StringBuilder :
StringBuilder builder = new StringBuilder();
for(File f : files) {
builder.append("<file>\n\t<fileName>").append(f.getName).append("</fileName>\n)";
[...]
}
System.out.println(builder.toString());