com.google.gwt.resources.ext

Interface ResourceContext

public interface ResourceContext

Context object for ResourceGenerators. An instance of this type will be provided by the resource generation framework to implementations of ResourceGenerator via ResourceGenerator.init(com.google.gwt.core.ext.TreeLogger, com.google.gwt.resources.ext.ResourceContext). Because this interface is not intended to be implemented by end-users, the API provided by this interface may be extended in the future.

Depending on the optimizations made by the implementation of deploy(java.lang.String, java.lang.String, byte[], boolean), the resulting URL may or may not be compatible with standard RequestBuilder / XMLHttpRequest security semantics. If the resource is intended to be used with XHR, or if there are other reasons why embedding the resource is undesirable such as known incompatibilities, the forceExternal parameter should be set to true when invoking deploy(java.lang.String, java.lang.String, byte[], boolean).

Method Summary

Modifier and Type	Method and Description
String	deploy(String suggestedFileName, String mimeType, byte[] data, boolean forceExternal) Cause a specific collection of bytes to be available in the program's compiled output.
String	deploy(URL resource, boolean forceExternal) Deprecated. use deploy(URL, String, boolean) instead
String	deploy(URL resource, String mimeType, boolean forceExternal) Cause a specific collection of bytes to be available in the program's compiled output.
<T> T	getCachedData(String key, Class<T> clazz) Retrieve data from the ResourceContext.
JClassType	getClientBundleType() Return the interface type of the resource bundle being generated.
GeneratorContext	getGeneratorContext() Return the GeneratorContext in which the overall resource generation framework is being run.
String	getImplementationSimpleSourceName() Returns the simple source name of the implementation of the bundle being generated.
ClientBundleRequirements	getRequirements() Returns a ClientBundleRequirements object, which can be used to track deferred-binding and configuration properties that are relevant to a resource context.
<T> boolean	putCachedData(String key, T value) Store data in the ResourceContext.
boolean	supportsDataUrls() Indicates if the runtime context supports data: urls.

Method Detail

deploy

String deploy(String suggestedFileName,
              String mimeType,
              byte[] data,
              boolean forceExternal)
       throws UnableToCompleteException

Cause a specific collection of bytes to be available in the program's compiled output. The return value of this method is a Java expression which will evaluate to the location of the resource at runtime. The exact format should not be depended upon.

Parameters:

suggestedFileName - an unobfuscated filename to possibly use for the resource

mimeType - the MIME type of the data being provided

data - the bytes to add to the output

forceExternal - prevents embedding of the resource, e.g. in case of known incompatibilities or for example to enforce compatibility with security restrictions if the resource is intended to be accessed via an XMLHttpRequest

Returns:

a Java expression which will evaluate to the location of the provided resource at runtime

Throws:

UnableToCompleteException

deploy

@Deprecated
String deploy(URL resource,
                          boolean forceExternal)
                   throws UnableToCompleteException

Deprecated. use deploy(URL, String, boolean) instead

Cause a specific collection of bytes to be available in the program's compiled output. The return value of this method is a Java expression which will evaluate to the location of the resource at runtime. The exact format should not be depended upon.

Parameters:

resource - the resource to add to the compiled output

forceExternal - prevents embedding of the resource, e.g. in case of known incompatibilities or for example to enforce compatibility with security restrictions if the resource is intended to be accessed via an XMLHttpRequest

Returns:

a Java expression which will evaluate to the location of the provided resource at runtime

Throws:

UnableToCompleteException

deploy

String deploy(URL resource,
              String mimeType,
              boolean forceExternal)
       throws UnableToCompleteException

Cause a specific collection of bytes to be available in the program's compiled output. The return value of this method is a Java expression which will evaluate to the location of the resource at runtime. The exact format should not be depended upon.

Parameters:

resource - the resource to add to the compiled output

mimeType - optional MIME Type to be used for an embedded resource

forceExternal - prevents embedding of the resource, e.g. in case of known incompatibilities or for example to enforce compatibility with security restrictions if the resource is intended to be accessed via an XMLHttpRequest

Returns:

a Java expression which will evaluate to the location of the provided resource at runtime

Throws:

UnableToCompleteException

getCachedData

<T> T getCachedData(String key,
                    Class<T> clazz)

Retrieve data from the ResourceContext.

Type Parameters:

T - the type of data to retrieve

Parameters:

key - the key value passed to getCachedData(java.lang.String, java.lang.Class<T>)

clazz - the type to which the cached value must be assignable

Returns:

the value previously passed to putCachedData(java.lang.String, T) or null if the data was not found

Throws:

ClassCastException - if the cached data is not assignable to the specified type

getClientBundleType

JClassType getClientBundleType()

Return the interface type of the resource bundle being generated.

getGeneratorContext

GeneratorContext getGeneratorContext()

Return the GeneratorContext in which the overall resource generation framework is being run. Implementations of ResourceGenerator should prefer deploy(java.lang.String, java.lang.String, byte[], boolean) over GeneratorContext.tryCreateResource(com.google.gwt.core.ext.TreeLogger, java.lang.String) in order to take advantage of serving optimizations that can be performed by the bundle architecture.

getImplementationSimpleSourceName

String getImplementationSimpleSourceName()
                                  throws IllegalStateException

Returns the simple source name of the implementation of the bundle being generated. This can be used during code-generation to refer to the instance of the bundle (e.g. via SimpleSourceName.this).

Throws:

IllegalStateException - if this method is called during ResourceGenerator.init(com.google.gwt.core.ext.TreeLogger, com.google.gwt.resources.ext.ResourceContext) or ResourceGenerator.prepare(com.google.gwt.core.ext.TreeLogger, com.google.gwt.resources.ext.ResourceContext, com.google.gwt.resources.ext.ClientBundleRequirements, com.google.gwt.core.ext.typeinfo.JMethod) methods.

getRequirements

ClientBundleRequirements getRequirements()

Returns a ClientBundleRequirements object, which can be used to track deferred-binding and configuration properties that are relevant to a resource context.

putCachedData

<T> boolean putCachedData(String key,
                          T value)

Store data in the ResourceContext. ResourceGenerators may reduce the amount of recomputation performed by caching data the ResourceContext. This cache will be invalidated when the compiler's TypeOracle is refreshed or replaced. Each ResourceGenerator has an isolated view of the cache.

Type Parameters:

T - the type of data being stored

Parameters:

key - a string key to locate the data

value - the value to store

Returns:

true if the cache did not previously contain the key-value pair

supportsDataUrls

boolean supportsDataUrls()

Indicates if the runtime context supports data: urls. When data URLs are supported by the context, aggregation of resource data into larger payloads is discouraged, as it offers reduced benefit to the application at runtime.