com.google.appengine.api.taskqueue
Class TaskOptions

java.lang.Object
  com.google.appengine.api.taskqueue.TaskOptions

All Implemented Interfaces:

java.io.Serializable

public final class TaskOptions
extends java.lang.Object
implements java.io.Serializable

Contains various options for a task following the builder pattern. Calls to TaskOptions methods may be chained to specify multiple options in the one TaskOptions object.

taskOptions can have either TaskOptions#Method PULL or a PUSH-related method, e.g. POST, GET, ... Tasks with PULL method can only be added into a PULL queue and PUSH tasks can only be added into a PUSH queue.

Notes on usage:
The recommended way to instantiate a TaskOptions object is to statically import TaskOptions.Builder.* and invoke a static creation method followed by an instance mutator (if needed):

 import static com.google.appengine.api.taskqueue.TaskOptions.Builder.*;

 ...
 QueueFactory.getDefaultQueue().add(header("X-HEADER", "value"));
 

See Also:

Serialized Form

Nested Class Summary

static class	TaskOptions.Builder Provides static creation methods for TaskOptions.
static class	TaskOptions.Method Methods supported by Queue.

Constructor Summary

TaskOptions(TaskOptions options)
A copy constructor for TaskOptions.

Method Summary

TaskOptions	clearParams() Clears the parameters.
TaskOptions	countdownMillis(long countdownMillis) Set the number of milliseconds delay before execution of the task.
boolean	equals(java.lang.Object obj)
TaskOptions	etaMillis(long etaMillis) Sets the approximate absolute time to execute.
java.lang.String	getUrl()
int	hashCode()
TaskOptions	header(java.lang.String headerName, java.lang.String value) Adds a header name/value pair.
TaskOptions	headers(java.util.Map<java.lang.String,java.lang.String> headers) Replaces the existing headers with the provided header name/value mapping.
TaskOptions	method(TaskOptions.Method method) Set the method used for this task.
TaskOptions	param(java.lang.String name, byte[] value) Add a named byte array parameter.
TaskOptions	param(java.lang.String name, java.lang.String value) Add a named String parameter.
TaskOptions	payload(byte[] payload) Sets the payload directly without specifying the content-type.
TaskOptions	payload(byte[] payload, java.lang.String contentType) Set the payload with the given content type.
TaskOptions	payload(DeferredTask deferredTask) Sets the payload to the serialized form of the deferredTask object.
TaskOptions	payload(java.lang.String payload) Set the payload by String.
TaskOptions	payload(java.lang.String payload, java.lang.String charset) Sets the payload from a String given a specific character set.
TaskOptions	removeHeader(java.lang.String headerName) Remove all headers with the given name.
TaskOptions	removeParam(java.lang.String paramName) Remove all parameters with the given name.
TaskOptions	retryOptions(RetryOptions retryOptions) Sets retry options for this task.
TaskOptions	taskName(java.lang.String taskName) Sets the task name.
java.lang.String	toString()
TaskOptions	url(java.lang.String url) Set the URL.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

TaskOptions

public TaskOptions(TaskOptions options)

A copy constructor for TaskOptions.

Method Detail

taskName

public TaskOptions taskName(java.lang.String taskName)

Sets the task name.

Throws:

java.lang.IllegalArgumentException - The provided name is null, empty or doesn't match the regular expression QueueConstants.TASK_NAME_REGEX

payload

public TaskOptions payload(byte[] payload)

Sets the payload directly without specifying the content-type. If this task is added to a push queue, the content-type will be set to 'application/octet-stream' by default.

Parameters:

payload - The bytes representing the paylaod.

Returns:

TaskOptions object for chaining.

payload

public TaskOptions payload(DeferredTask deferredTask)

Sets the payload to the serialized form of the deferredTask object. The payload will be generated by serializing the deferredTask object using ObjectOutputStream.writeObject(Object). If the deferredTask's TaskOptions.Method is not PULL, the content type will be set to DeferredTaskContext.RUNNABLE_TASK_CONTENT_TYPE, the method will be forced to TaskOptions.Method.POST and if otherwise not specified, the url will be set to DeferredTaskContext.DEFAULT_DEFERRED_URL; the DeferredTask servlet is, by default, mapped to this url.

Note: While this may be a convenient API, it requires careful control of the serialization compatibility of objects passed into payload(DeferredTask) method as objects placed in the task queue will survive revision updates of the application and hence may fail deserialization when the task is decoded with new revisions of the application. In particular, Java anonymous classes are convenient but may be particularly difficult to control or test for serialization compatibility.

Parameters:

deferredTask - The object to serialize into the payload.

Throws:

DeferredTaskCreationException - if there was an IOException serializing object.

payload

public TaskOptions payload(java.lang.String payload,
                           java.lang.String charset)

Sets the payload from a String given a specific character set.

Throws:

UnsupportedTranslationException

payload

public TaskOptions payload(byte[] payload,
                           java.lang.String contentType)

Set the payload with the given content type.

Parameters:

payload - The bytes representing the paylaod.

contentType - The content-type of the bytes.

Returns:

TaskOptions object for chaining.

payload

public TaskOptions payload(java.lang.String payload)

Set the payload by String. The charset to convert the String to will be UTF-8 unless the method is PULL, in which case the String's bytes will be used directly.

Parameters:

payload - The String to be used.

Returns:

TaskOptions object for chaining.

headers

public TaskOptions headers(java.util.Map<java.lang.String,java.lang.String> headers)

Replaces the existing headers with the provided header name/value mapping.

Parameters:

headers - The headers to copy.

Returns:

TaskOptions object for chaining.

header

public TaskOptions header(java.lang.String headerName,
                          java.lang.String value)

Adds a header name/value pair.

Throws:

java.lang.IllegalArgumentException

removeHeader

public TaskOptions removeHeader(java.lang.String headerName)

Remove all headers with the given name.

method

public TaskOptions method(TaskOptions.Method method)

Set the method used for this task. Defaults to TaskOptions.Method.POST.

clearParams

public TaskOptions clearParams()

Clears the parameters.

param

public TaskOptions param(java.lang.String name,
                         java.lang.String value)

Add a named String parameter.

Parameters:

name - Name of the parameter. Must not be null or empty.

value - The value of the parameter will undergo a "UTF-8" character encoding transformation upon being added to the queue. value must not be null.

Throws:

java.lang.IllegalArgumentException

param

public TaskOptions param(java.lang.String name,
                         byte[] value)

Add a named byte array parameter.

Parameters:

name - Name of the parameter. Must not be null or empty.

value - A byte array and encoded as-is (i.e. without character encoding transformations). value must not be null.

Throws:

java.lang.IllegalArgumentException

removeParam

public TaskOptions removeParam(java.lang.String paramName)

Remove all parameters with the given name.

Parameters:

paramName - Name of the parameter. Must not be null or empty.

getUrl

public java.lang.String getUrl()

url

public TaskOptions url(java.lang.String url)

Set the URL.

Default value is null.

Parameters:

url - String containing URL.

countdownMillis

public TaskOptions countdownMillis(long countdownMillis)

Set the number of milliseconds delay before execution of the task.

etaMillis

public TaskOptions etaMillis(long etaMillis)

Sets the approximate absolute time to execute. (i.e. etaMillis is comparable with System.currentTimeMillis()).

retryOptions

public TaskOptions retryOptions(RetryOptions retryOptions)

Sets retry options for this task. Retry Options must be built with RetryOptions.Builder.

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object