|
 |
|
|
org.eclipse.core.runtime.content
Class BinarySignatureDescriber
java.lang.Object
org.eclipse.core.runtime.content.BinarySignatureDescriber
-
All Implemented Interfaces:
-
IContentDescriber,
IExecutableExtension
-
public final class BinarySignatureDescriber
- extends
Object
- implements
IContentDescriber,
IExecutableExtension
A content describer for binary formats that present some
simple signature at a known, fixed offset.
This executable extension supports three parameters:
"signature", "offset" and "required", the first one being mandatory.
If the
":-" method is used, then the value is treated as the
"signature".
The "signature" parameter is a sequence of hex codes, one for each byte in
the signature. For example, "CA FE BA BE" would be a signature for Java
class files.
The "offset" parameter is an integer indicating the offset where the
signature's first byte is found.
The "required" parameter is a boolean (default is " true") indicating whether
the absence of a signature should deem the contents validity status as
IContentDescriber.INVALID or IContentDescriber.INDETERMINATE.
This class is not intended to be subclassed or instantiated by clients,
only to be referenced by the "describer" configuration element in
extensions to the org.eclipse.core.runtime.contentTypes
extension point.
-
Since:
- 3.0
Methods inherited from class java.lang.
Object
|
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait
|
BinarySignatureDescriber
public BinarySignatureDescriber()
describe
public int describe(
InputStream contents,
IContentDescription description)
throws
IOException
-
Description copied from interface:
IContentDescriber
- Tries to fill a description for the given contents. Returns
an
int indicating whether the given stream of
bytes represents a valid sample for its corresponding content type.
If no content description is provided, this method should perform
content type validation.
The input stream must be kept open, and any IOExceptions while
reading the stream should flow to the caller.
-
-
Specified by:
-
describe
in interface
IContentDescriber
-
-
Parameters:
-
contents - the contents to be examined -
description - a description to be filled in, or null if
only content type validation is to be performed
-
Returns:
- one of the following:
-
VALID
,
-
INVALID
,
-
INDETERMINATE
-
Throws:
-
IOException
- if an I/O error occurs -
See Also:
-
IContentDescription ,
IContentDescriber.VALID ,
IContentDescriber.INVALID ,
IContentDescriber.INDETERMINATE
getSupportedOptions
public
QualifiedName[] getSupportedOptions()
-
Description copied from interface:
IContentDescriber
- Returns the properties supported by this describer.
-
-
Specified by:
-
getSupportedOptions
in interface
IContentDescriber
-
-
Returns:
- the supported properties
-
See Also:
-
IContentDescriber.describe(java.io.InputStream, org.eclipse.core.runtime.content.IContentDescription)
setInitializationData
public void setInitializationData(
IConfigurationElement config,
String propertyName,
Object data)
throws
CoreException
-
Description copied from interface:
IExecutableExtension
- This method is called by the implementation of the method
IConfigurationElement.createExecutableExtension
on a newly constructed extension, passing it its relevant configuration
information. Most executable extensions only make use of the first
two call arguments.
Regular executable extensions specify their Java implementation
class name as an attribute of the configuration element for the
extension. For example
<action run="com.example.BaseAction"/>
In the above example, this method would be called with a reference
to the <action> element (first argument), and
"run" as the name of the attribute that defined
this executable extension (second argument).
The last parameter is for the specific use of extension adapters
and is typically not used by regular executable extensions.
There are two supported ways of associating additional
adapter-specific data with the configuration in a way that
is transparent to the extension point implementor:
(1) by specifying adapter data as part of the implementation
class attribute value. The Java class name can be followed
by a ":" separator, followed by any adapter data in string
form. For example, if the extension point specifies an attribute
"run" to contain the name of the extension implementation,
an adapter can be configured as
<action run="com.example.ExternalAdapter:./cmds/util.exe -opt 3"/>
(2) by converting the attribute used to specify the executable
extension to a child element of the original configuration element,
and specifying the adapter data in the form of xml markup.
Using this form, the example above would become
<action>
<run class="com.xyz.ExternalAdapter">
<parameter name="exec" value="./cmds/util.exe"/>
<parameter name="opt" value="3"/>
</run>
</action>
Form (2) will typically only be
used for extension points that anticipate the majority of
extensions configured into it will in fact be in the form
of adapters.
In either case, the specified adapter class is instantiated using its
0-argument public constructor. The adapter data is passed as the
last argument of this method. The data argument is defined as Object.
It can have the following values:
-
null , if no adapter data was supplied
- in case (1), the initialization data
string is passed as a
String
- in case (2), the initialization data is passed
as a
Hashtable containing the actual
parameter names and values (both String s)
-
-
Specified by:
-
setInitializationData
in interface
IExecutableExtension
-
-
Parameters:
-
config - the configuration element used to trigger this execution.
It can be queried by the executable extension for specific
configuration properties -
propertyName - the name of an attribute of the configuration element
used on the createExecutableExtension(String) call. This
argument can be used in the cases where a single configuration element
is used to define multiple executable extensions. -
data - adapter data in the form of a String ,
a Hashtable , or null .
-
Throws:
-
CoreException
- if error(s) detected during initialization processing -
See Also:
-
IConfigurationElement.createExecutableExtension(String)
Guidelines for using Eclipse APIs.
Copyright (c) Eclipse contributors and others 2000, 2008. All rights reserved.
|
|
|