groovy.yaml

Class YamlBuilder

java.lang.Object

groovy.lang.GroovyObjectSupport

groovy.yaml.YamlBuilder

All Implemented Interfaces:

GroovyObject, Writable

public class YamlBuilder
extends GroovyObjectSupport
implements Writable

A builder for creating YAML payloads.

Since:

3.0.0

Constructor Summary

Constructors

Constructor and Description
YamlBuilder()

Method Summary

Modifier and Type	Method and Description
Object	call(Closure c) A closure passed to a YAML builder will create a root YAML object
Object	call(Collection coll, Closure c) Delegates to call(Iterable, Closure)
Object	call(Iterable coll, Closure c) A collection and closure passed to a YAML builder will create a root YAML array applying the closure to each object in the collection
Object	call(List l) A list of elements as arguments to the YAML builder creates a root YAML array
Object	call(Map m) Named arguments can be passed to the YAML builder instance to create a root YAML object
Object	call(Object... args) Varargs elements as arguments to the YAML builder create a root YAML array
Object	getContent()
Object	invokeMethod(String name, Object args) A method call on the YAML builder instance will create a root object with only one key whose name is the name of the method being called.
String	toString() Serializes the internal data structure built with the builder to a conformant YAML payload string
Writer	writeTo(Writer out) The YAML builder implements the Writable interface, so that you can have the builder serialize itself the YAML payload to a writer.

Methods inherited from class groovy.lang.GroovyObjectSupport

getMetaClass, setMetaClass

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface groovy.lang.GroovyObject

getProperty, setProperty

Constructor Detail

YamlBuilder

public YamlBuilder()

Method Detail

getContent

public Object getContent()

call

public Object call(Map m)

Named arguments can be passed to the YAML builder instance to create a root YAML object

Example:

 def yaml = new groovy.yaml.YamlBuilder()
 yaml name: "Guillaume", age: 33

 assert yaml.toString() == '''---
 name: "Guillaume"
 age: 33
 '''
 

Parameters:

m - a map of key / value pairs

Returns:

a map of key / value pairs

call

public Object call(List l)

A list of elements as arguments to the YAML builder creates a root YAML array

Example:

 def yaml = new groovy.yaml.YamlBuilder()
 def result = yaml([1, 2, 3])

 assert result instanceof List
 assert yaml.toString() == '''---
 - 1
 - 2
 - 3
 '''
 

Parameters:

l - a list of values

Returns:

a list of values

call

public Object call(Object... args)

Varargs elements as arguments to the YAML builder create a root YAML array

Example:

 def yaml = new groovy.yaml.YamlBuilder()
 def result = yaml 1, 2, 3

 assert result instanceof List
 assert yaml.toString() == '''---
 - 1
 - 2
 - 3
 '''
 

Parameters:

args - an array of values

Returns:

a list of values

call

public Object call(Iterable coll,
                   Closure c)

A collection and closure passed to a YAML builder will create a root YAML array applying the closure to each object in the collection

Example:

 class Author {
      String name
 }
 def authors = [new Author (name: "Guillaume"), new Author (name: "Jochen"), new Author (name: "Paul")]

 def yaml = new groovy.yaml.YamlBuilder()
 yaml authors, { Author author  ->
      name author.name
 }

 assert yaml.toString() == '''---
 - name: "Guillaume"
 - name: "Jochen"
 - name: "Paul"
 '''
 

Parameters:

coll - a collection

c - a closure used to convert the objects of coll

Returns:

a list of values

call

public Object call(Collection coll,
                   Closure c)

Delegates to call(Iterable, Closure)

Parameters:

coll -

c -

call

public Object call(Closure c)

A closure passed to a YAML builder will create a root YAML object

Example:

 def yaml = new groovy.yaml.YamlBuilder()
 def result = yaml {
      name "Guillaume"
      age 33
 }

 assert result instanceof Map
 assert yaml.toString() == '''---
 name: "Guillaume"
 age: 33
 '''
 

Parameters:

c - a closure whose method call statements represent key / values of a YAML object

Returns:

a map of key / value pairs

invokeMethod

public Object invokeMethod(String name,
                           Object args)

A method call on the YAML builder instance will create a root object with only one key whose name is the name of the method being called. This method takes as arguments:

• a closure
• a map (ie. named arguments)
• a map and a closure
• or no argument at all

Example with a classical builder-style:

 def yaml = new groovy.yaml.YamlBuilder()
 def result = yaml.person {
      name "Guillaume"
      age 33
 }

 assert result instanceof Map
 assert yaml.toString() == '''---
 person:
   name: "Guillaume"
   age: 33
 '''
 

Or alternatively with a method call taking named arguments:

 def yaml = new groovy.yaml.YamlBuilder()
 yaml.person name: "Guillaume", age: 33

 assert yaml.toString() == '''---
 person:
   name: "Guillaume"
   age: 33
 '''
 

If you use named arguments and a closure as last argument, the key/value pairs of the map (as named arguments) and the key/value pairs represented in the closure will be merged together — the closure properties overriding the map key/values in case the same key is used.

 def yaml = new groovy.yaml.YamlBuilder()
 yaml.person(name: "Guillaume", age: 33) { town "Paris" }

 assert yaml.toString() == '''---
 person:
   name: "Guillaume"
   age: 33
   town: "Paris"
 '''
 

The empty args call will create a key whose value will be an empty YAML object:

 def yaml = new groovy.yaml.YamlBuilder()
 yaml.person()

 assert yaml.toString() == '''---
 person: {}
 '''
 

Specified by:

invokeMethod in interface GroovyObject

Parameters:

name - the single key

args - the value associated with the key

Returns:

a map with a single key

toString

public String toString()

Serializes the internal data structure built with the builder to a conformant YAML payload string

Example:

 def yaml = new groovy.yaml.YamlBuilder()
 yaml { temperature 37 }

 assert yaml.toString() == '''---
 temperature: 37
 '''
 

Overrides:

toString in class Object

Returns:

a YAML output

writeTo

public Writer writeTo(Writer out)
               throws IOException

The YAML builder implements the Writable interface, so that you can have the builder serialize itself the YAML payload to a writer.

Example:

 def yaml = new groovy.yaml.YamlBuilder()
 yaml { temperature 37 }

 def out = new StringWriter()
 out  << yaml

 assert out.toString() == '''---
 temperature: 37
 '''
 

Specified by:

writeTo in interface Writable

Parameters:

out - a writer on which to serialize the YAML payload

Returns:

the writer

Throws:

IOException - if an error occurred while outputting data to the writer