org.apache.tools.ant.util
public class ClasspathUtils extends Object
The basic idea behind this utility class is to use it from inside the different Ant objects (and user defined objects) that need classLoading for their operation. Normally those would have a setClasspathRef() {for the @classpathref} and/or a createClasspath() {for the nested <classpath>} Typically one would have in your Ant Task or DataType
ClasspathUtils.Delegate cpDelegate;
public void init() {
this.cpDelegate = ClasspathUtils.getDelegate(this);
super.init();
}
public void setClasspathRef(Reference r) {
this.cpDelegate.setClasspathRef(r);
}
public Path createClasspath() {
return this.cpDelegate.createClasspath();
}
public void setClassname(String fqcn) {
this.cpDelegate.setClassname(fqcn);
}
At execution time, when you actually need the classloading you can just:
Object o = this.cpDelegate.newInstance();
Since: Ant 1.6
Nested Class Summary | |
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static class | ClasspathUtils.Delegate
Delegate that helps out any specific ProjectComponent that needs
dynamic classloading.
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Field Summary | |
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static String | REUSE_LOADER_REF
Name of the magic property that controls classloader reuse in Ant 1.4. |
Method Summary | |
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static ClassLoader | getClassLoaderForPath(Project p, Reference ref)
Convenience overloaded version of {@link
#getClassLoaderForPath(Project, Reference, boolean)}.
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static ClassLoader | getClassLoaderForPath(Project p, Reference ref, boolean reverseLoader)
Convenience overloaded version of {@link #getClassLoaderForPath(Project, Path,
String, boolean)}.
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static ClassLoader | getClassLoaderForPath(Project p, Path path, String loaderId)
Convenience overloaded version of {@link
#getClassLoaderForPath(Project, Path, String, boolean)}.
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static ClassLoader | getClassLoaderForPath(Project p, Path path, String loaderId, boolean reverseLoader)
Convenience overloaded version of {@link
#getClassLoaderForPath(Project, Path, String, boolean, boolean)}.
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static ClassLoader | getClassLoaderForPath(Project p, Path path, String loaderId, boolean reverseLoader, boolean reuseLoader)
Gets a classloader that loads classes from the classpath
defined in the path argument.
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static ClasspathUtils.Delegate | getDelegate(ProjectComponent component)
Obtains a delegate that helps out with classic classpath configuration.
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static ClassLoader | getUniqueClassLoaderForPath(Project p, Path path, boolean reverseLoader)
Gets a fresh, different, previously unused classloader that uses the
passed path as its classpath.
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static Object | newInstance(String className, ClassLoader userDefinedLoader)
Creates a fresh object instance of the specified classname.
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static Object | newInstance(String className, ClassLoader userDefinedLoader, Class expectedType)
Creates a fresh object instance of the specified classname.
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Assumes the logical 'false' for the reverseLoader.
Parameters: p the project ref the reference
Returns: The class loader
Delegates to the other one after extracting the referenced Path from the Project. This checks also that the passed Reference is pointing to a Path all right.
Parameters: p current Ant project ref Reference to Path structure reverseLoader if set to true this new loader will take precedence over its parent (which is contra the regular classloader behaviour)
Returns: The class loader
Assumes the logical 'false' for the reverseLoader.
Parameters: p current Ant project path the path loaderId the loader id string
Returns: The class loader
Sets value for 'reuseLoader' to true if the magic property has been set.
Parameters: p the project path the path loaderId the loader id string reverseLoader if set to true this new loader will take precedence over its parent (which is contra the regular classloader behaviour)
Returns: The class loader
Based on the setting of the magic property 'ant.reuse.loader' this will try to reuse the previously created loader with that id, and of course store it there upon creation.
Parameters: p Ant Project where the handled components are living in. path Path object to be used as classpath for this classloader loaderId identification for this Loader, reverseLoader if set to true this new loader will take precedence over its parent (which is contra the regular classloader behaviour) reuseLoader if true reuse the loader if it is found
Returns: ClassLoader that uses the Path as its classpath.
Parameters: component your projectComponent that needs the assistence
Returns: the helper, delegate.
See Also: Delegate
This method completely ignores the ant.reuse.loader magic property and should be used with caution.
Parameters: p Ant Project where the handled components are living in. path the classpath for this loader reverseLoader if set to true this new loader will take precedence over its parent (which is contra the regular classloader behaviour)
Returns: The fresh, different, previously unused class loader.
This uses the userDefinedLoader to load the specified class, and then makes an instance using the default no-argument constructor.
Parameters: className the full qualified class name to load. userDefinedLoader the classloader to use.
Returns: The fresh object instance
Throws: BuildException when loading or instantiation failed.
This uses the userDefinedLoader to load the specified class, and then makes an instance using the default no-argument constructor.
Parameters: className the full qualified class name to load. userDefinedLoader the classloader to use. expectedType the Class that the result should be assignment compatible with. (No ClassCastException will be thrown in case the result of this method is casted to the expectedType)
Returns: The fresh object instance
Throws: BuildException when loading or instantiation failed.
Since: Ant 1.7