org.eclipse.core.expressions
Class PropertyTester
java.lang.Object
org.eclipse.core.expressions.PropertyTester
-
All Implemented Interfaces:
-
IPropertyTester
-
public abstract class PropertyTester
- extends
Object
- implements
IPropertyTester
Abstract superclass of all property testers. Implementation classes of
the extension point org.eclipse.core.expresssions.propertyTesters
must extend PropertyTester.
A property tester implements the property tests enumerated in the property
tester extension point. For the following property test extension
<propertyTester
namespace="org.eclipse.jdt.core"
id="org.eclipse.jdt.core.IPackageFragmentTester"
properties="isDefaultPackage"
type="org.eclipse.jdt.core.IPackageFragment"
class="org.eclipse.demo.MyPackageFragmentTester">
</propertyTester>
the corresponding implementation class looks like:
public class MyPackageFragmentTester {
public boolean test(Object receiver, String property, Object[] args, Object expectedValue) {
IPackageFragment fragment= (IPackageFragment)receiver;
if ("isDefaultPackage".equals(property)) {
return expectedValue == null
? fragment.isDefaultPackage()
: fragment.isDefaultPackage() == ((Boolean)expectedValue).booleanValue();
}
Assert.isTrue(false);
return false;
}
}
The property can then be used in a test expression as follows:
<instanceof value="org.eclipse.core.IPackageFragment"/>
<test property="org.eclipse.jdt.core.isDefaultPackage"/>
There is no guarantee that the same instance of a property tester is used
to handle <test property="..."/> requests. So property testers
should always be implemented in a stateless fashion.
-
Since:
- 3.0
|
Method Summary
|
boolean
|
handles
(
String namespace,
String property)
Returns whether the property tester can handle the given
property or not. |
IPropertyTester
|
instantiate
()
Loads the implementation class for this property tester and returns an
instance of this class. |
org.eclipse.core.internal.expressions.PropertyTesterDescriptor
|
internalCreateDescriptor
()
Note: this method is for internal use only. |
void
|
internalInitialize
(org.eclipse.core.internal.expressions.PropertyTesterDescriptor descriptor)
Initialize the property tester with the given name space and property. |
boolean
|
isDeclaringPluginActive
()
Returns true if the implementation class of this property
tester can be loaded. |
boolean
|
isInstantiated
()
Returns whether the implementation class for this property tester is
loaded or not. |
|
Methods inherited from class java.lang.
Object
|
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait
|
PropertyTester
public PropertyTester()
internalInitialize
public final void internalInitialize(org.eclipse.core.internal.expressions.PropertyTesterDescriptor descriptor)
- Initialize the property tester with the given name space and property.
Note: this method is for internal use only. Clients must not call
this method.
-
-
-
Parameters:
-
descriptor - the descriptor object for this tester -
Restriction:
- This method is not intended to be referenced by clients.
internalCreateDescriptor
public final org.eclipse.core.internal.expressions.PropertyTesterDescriptor internalCreateDescriptor()
- Note: this method is for internal use only. Clients must not call
this method.
-
-
-
Returns:
- the property tester descriptor
-
Restriction:
- This method is not intended to be referenced by clients.
handles
public final boolean handles(
String namespace,
String property)
- Returns whether the property tester can handle the given
property or not.
-
-
Specified by:
-
handles
in interface
IPropertyTester
-
-
Parameters:
-
namespace - the name space to be considered -
property - the property to test
-
Returns:
-
true if the tester provides an implementation
for the given property; otherwise false is returned
isInstantiated
public final boolean isInstantiated()
- Returns whether the implementation class for this property tester is
loaded or not.
-
-
Specified by:
-
isInstantiated
in interface
IPropertyTester
-
-
Returns:
-
trueif the implementation class is loaded;
false otherwise
isDeclaringPluginActive
public boolean isDeclaringPluginActive()
- Returns
true if the implementation class of this property
tester can be loaded. This is the case if the plug-in providing
the implementation class is active. Returns false otherwise.
-
-
Specified by:
-
isDeclaringPluginActive
in interface
IPropertyTester
-
-
Returns:
- whether the implementation class can be loaded or not
instantiate
public final
IPropertyTester instantiate()
- Loads the implementation class for this property tester and returns an
instance of this class.
-
-
Specified by:
-
instantiate
in interface
IPropertyTester
-
-
Returns:
- an instance of the implementation class for this property tester
Guidelines for using Eclipse APIs.
Copyright (c) Eclipse contributors and others 2000, 2008. All rights reserved.
