groovyx.net.http

Class EncoderRegistry

java.lang.Object

groovyx.net.http.EncoderRegistry

All Implemented Interfaces:

Iterable<Map.Entry<String,Closure>>

public class EncoderRegistry
extends Object
implements Iterable<Map.Entry<String,Closure>>

This class handles creation of the request body (i.e. for a PUT or POST operation) based on content-type. When a body is set from the builder, it is processed based on the request content-type. For instance, the encodeForm(Map) method will be invoked if the request content-type is form-urlencoded, which will cause the following:body=[a:1, b:'two'] to be encoded as the equivalent a=1&b=two in the request body.

Most default encoders can handle a closure as a request body. In this case, the closure is executed and a suitable 'builder' passed to the closure that is used for constructing the content. In the case of binary encoding this would be an OutputStream; for TEXT encoding it would be a PrintWriter, and for XML it would be an already-bound StreamingMarkupBuilder. See each encode... method for details for each particular content-type.

Contrary to its name, this class does not have anything to do with the content-encoding HTTP header.

Author:

Tom Nichols

See Also:

HTTPBuilder.RequestConfigDelegate.setBody(Object), HTTPBuilder.RequestConfigDelegate.send(Object, Object)

Constructor Summary

Constructors

Constructor and Description
EncoderRegistry()

Method Summary

Methods

Modifier and Type	Method and Description
protected Map<String,Closure>	buildDefaultEncoderMap() Returns a map of default encoders.
protected StringEntity	createEntity(Object ct, String data) Helper method used by encoder methods to create an HttpEntity instance that encapsulates the request data.
UrlEncodedFormEntity	encodeForm(Map<?,?> params) Set the request body as a url-encoded list of parameters.
UrlEncodedFormEntity	encodeForm(Map<?,?> params, Object contentType)
HttpEntity	encodeForm(String formData, Object contentType) Accepts a String as a url-encoded form post.
HttpEntity	encodeJSON(Object model, Object contentType) Accepts a Collection or a JavaBean object which is converted to JSON.
InputStreamEntity	encodeStream(Object data, Object contentType) Default request encoder for a binary stream.
HttpEntity	encodeText(Object data, Object contentType) Default handler used for a plain text content-type.
HttpEntity	encodeXML(Object xml, Object contentType) Encode the content as XML.
Closure	getAt(Object contentType) Retrieve a encoder for the given content-type.
Iterator<Map.Entry<String,Closure>>	iterator() Iterate over the entire parser map
Closure	propertyMissing(Object key) Alias for getAt(Object) to allow property-style access.
void	propertyMissing(Object key, Closure value) Alias for putAt(Object, Closure) to allow property-style access.
void	putAt(Object contentType, Closure value) Register a new encoder for the given content type.
void	setCharset(String charset) Set the charset used in the content-type header of all requests that send textual data.

Methods inherited from class java.lang.Object

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

Constructor Detail

EncoderRegistry

public EncoderRegistry()

Method Detail

setCharset

public void setCharset(String charset)

Set the charset used in the content-type header of all requests that send textual data. This must be a chaset supported by the Java platform

Parameters:

charset -

See Also:

Charset.forName(String)

encodeStream

public InputStreamEntity encodeStream(Object data,
                             Object contentType)
                               throws UnsupportedEncodingException

Default request encoder for a binary stream. Acceptable argument types are:

• InputStream
• byte[] / ByteArrayOutputStream
• Closure

If a closure is given, it is executed with an OutputStream passed as the single closure argument. Any data sent to the stream from the body of the closure is used as the request content body.

Parameters:

data -

Returns:

an HttpEntity encapsulating this request data

Throws:

UnsupportedEncodingException

encodeText

public HttpEntity encodeText(Object data,
                    Object contentType)
                      throws IOException

Default handler used for a plain text content-type. Acceptable argument types are:

• Closure
• Writable
• Reader

For Closure argument, a PrintWriter is passed as the single argument to the closure. Any data sent to the writer from the closure will be sent to the request content body.

Parameters:

data -

Returns:

an HttpEntity encapsulating this request data

Throws:

IOException

encodeForm

public UrlEncodedFormEntity encodeForm(Map<?,?> params)
                                throws UnsupportedEncodingException

Set the request body as a url-encoded list of parameters. This is typically used to simulate a HTTP form POST. For multi-valued parameters, enclose the values in a list, e.g.

[ key1 : ['val1', 'val2'], key2 : 'etc.' ]

Parameters:

params -

Returns:

an HttpEntity encapsulating this request data

Throws:

UnsupportedEncodingException

encodeForm

public UrlEncodedFormEntity encodeForm(Map<?,?> params,
                              Object contentType)
                                throws UnsupportedEncodingException

Throws:

UnsupportedEncodingException

encodeForm

public HttpEntity encodeForm(String formData,
                    Object contentType)
                      throws UnsupportedEncodingException

Accepts a String as a url-encoded form post. This method assumes the String is an already-encoded POST string.

Parameters:

formData - a url-encoded form POST string. See The W3C spec for more info.

Returns:

an HttpEntity encapsulating this request data

Throws:

UnsupportedEncodingException

encodeXML

public HttpEntity encodeXML(Object xml,
                   Object contentType)
                     throws UnsupportedEncodingException

Encode the content as XML. The argument may be either an object whose toString produces valid markup, or a Closure which will be interpreted as a builder definition. A closure argument is passed to StreamingMarkupBuilder#bind(groovy.lang.Closure).

Parameters:

xml - data that defines the XML structure

Returns:

an HttpEntity encapsulating this request data

Throws:

UnsupportedEncodingException

encodeJSON

public HttpEntity encodeJSON(Object model,
                    Object contentType)
                      throws UnsupportedEncodingException

Accepts a Collection or a JavaBean object which is converted to JSON. A Map or POJO/POGO will be converted to a JSONObject, and any other collection type will be converted to a JSONArray. A String or GString will be interpreted as valid JSON and passed directly as the request body (with charset conversion if necessary.)

If a Closure is passed as the model, it will be executed as if it were a JSON object definition passed to a JsonGroovyBuilder. In order for the closure to be interpreted correctly, there must be a 'root' element immediately inside the closure. For example:

builder.post( JSON ) {
   body = {
     root {
       first {
         one = 1
         two = '2'
       }
       second = 'some string'
     }
   }
 }

will return the following JSON string:

 {"root":{"first":{"one":1,"two":"2"},"second":"some string"}}

Parameters:

model - data to be converted to JSON, as specified above.

Returns:

an HttpEntity encapsulating this request data

Throws:

UnsupportedEncodingException

createEntity

protected StringEntity createEntity(Object ct,
                        String data)
                             throws UnsupportedEncodingException

Helper method used by encoder methods to create an HttpEntity instance that encapsulates the request data. This may be used by any non-streaming encoder that needs to send textual data. It also sets the charset portion of the content-type header.

Parameters:

ct - content-type of the data

data - textual request data to be encoded

Returns:

an instance to be used for the request content

Throws:

UnsupportedEncodingException

buildDefaultEncoderMap

protected Map<String,Closure> buildDefaultEncoderMap()

Returns a map of default encoders. Override this method to change what encoders are registered by default. You can of course call super.buildDefaultEncoderMap() and then add or remove from that result as well.

getAt

public Closure getAt(Object contentType)

Retrieve a encoder for the given content-type. This is called by HTTPBuilder to retrieve the correct encoder for a given content-type. The encoder is then used to serialize the request data in the request body.

Parameters:

contentType -

Returns:

encoder that can interpret the given content type, or null.

putAt

public void putAt(Object contentType,
         Closure value)

Register a new encoder for the given content type. If any encoder previously existed for that content type it will be replaced. The closure must return an HttpEntity. It will also usually accept a single argument, which will be whatever is set in the request configuration closure via HTTPBuilder.RequestConfigDelegate.setBody(Object).

Parameters:

contentType -

closure -

propertyMissing

public Closure propertyMissing(Object key)

Alias for getAt(Object) to allow property-style access.

Parameters:

key -

Returns:

propertyMissing

public void propertyMissing(Object key,
                   Closure value)

Alias for putAt(Object, Closure) to allow property-style access.

Parameters:

key -

value -

iterator

public Iterator<Map.Entry<String,Closure>> iterator()

Iterate over the entire parser map

Specified by:

iterator in interface Iterable<Map.Entry<String,Closure>>

Returns: