/**
* Find a package by name in the callers {@code ClassLoader} instance. The callers {@code
* ClassLoader} instance is used to find the package instance corresponding to the named class. If
* the callers {@code ClassLoader} instance is null then the set of packages loaded by the system
* {@code ClassLoader} instance is searched to find the named package.
*
* <p>Packages have attributes for versions and specifications only if the class loader created
* the package instance with the appropriate attributes. Typically, those attributes are defined
* in the manifests that accompany the classes.
*
* @param name a package name, for example, java.lang.
* @return the package of the requested name. It may be null if no package information is
* available from the archive or codebase.
*/
public static Package getPackage(String name) {
ClassLoader l = ClassLoader.getCallerClassLoader();
if (l != null) {
return l.getPackage(name);
} else {
return getSystemPackage(name);
}
}
/**
* Returns the {@code Package} of which the class represented by this {@code Class} is a member.
* Returns {@code null} if no {@code Package} object was created by the class loader of the class.
*
* @return Package the {@code Package} of which this {@code Class} is a member or {@code null}.
*/
public Package getPackage() {
// TODO This might be a hack, but the VM doesn't have the necessary info.
ClassLoader loader = getClassLoader();
if (loader != null) {
String name = getName();
int dot = name.lastIndexOf('.');
return (dot != -1 ? loader.getPackage(name.substring(0, dot)) : null);
}
return null;
}
/**
* Get the package for the specified class. The class's class loader is used to find the package
* instance corresponding to the specified class. If the class loader is the bootstrap class
* loader, which may be represented by {@code null} in some implementations, then the set of
* packages loaded by the bootstrap class loader is searched to find the package.
*
* <p>Packages have attributes for versions and specifications only if the class loader created
* the package instance with the appropriate attributes. Typically those attributes are defined in
* the manifests that accompany the classes.
*
* @param class the class to get the package of.
* @return the package of the class. It may be null if no package information is available from
* the archive or codebase.
*/
static Package getPackage(Class<?> c) {
String name = c.getName();
int i = name.lastIndexOf('.');
if (i != -1) {
name = name.substring(0, i);
ClassLoader cl = c.getClassLoader();
if (cl != null) {
return cl.getPackage(name);
} else {
return getSystemPackage(name);
}
} else {
return null;
}
}
public Package getPackage() {
ClassLoader cl = type.getClassLoader();
return cl.getPackage(getPackageName());
}