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*
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*
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* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
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* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
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* language governing permissions and limitations under the License.
*
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* file and include the License file at packager/legal/LICENSE.txt.
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* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
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package javax.el;
import java.util.
Map;
import java.util.
List;
import java.util.
HashMap;
import java.util.
ArrayList;
import java.util.
HashSet;
import java.lang.reflect.
Modifier;
/**
* Handles imports of class names and package names. An imported package
* name implicitly imports all the classes in the package. A class that has
* been imported can be used without its package name.
* The name is resolved to its full (package and class) name
* at evaluation time.
*/
public class
ImportHandler {
private
Map<
String,
String>
classNameMap = new
HashMap<
String,
String>();
private
Map<
String,
Class<?>>
classMap = new
HashMap<
String,
Class<?>>();
private
Map<
String,
String>
staticNameMap = new
HashMap<
String,
String>();
private
HashSet<
String>
notAClass = new
HashSet<
String>();
private
List<
String>
packages = new
ArrayList<
String>();
{
importPackage("java.lang");
}
/**
* Import a static field or method.
* @param name The static member name, including the full class name,
* to be imported
* @throws ELException if the name does not include a ".".
*/
public void
importStatic(
String name) throws
ELException {
int
i =
name.
lastIndexOf('.');
if (
i <= 0) {
throw new
ELException(
"The name " +
name + " is not a full static member name");
}
String memberName =
name.
substring(
i+1);
String className =
name.
substring(0,
i);
staticNameMap.
put(
memberName,
className);
}
/**
* Import a class.
* @param name The full class name of the class to be imported
* @throws ELException if the name does not include a ".".
*/
public void
importClass(
String name) throws
ELException {
int
i =
name.
lastIndexOf('.');
if (
i <= 0) {
throw new
ELException(
"The name " +
name + " is not a full class name");
}
String className =
name.
substring(
i+1);
classNameMap.
put(
className,
name);
}
/**
* Import all the classes in a package.
* @param packageName The package name to be imported
*/
public void
importPackage(
String packageName) {
packages.
add(
packageName);
}
/**
* Resolve a class name.
*
* @param name The name of the class (without package name) to be resolved.
* @return If the class has been imported previously, with
* {@link #importClass} or {@link #importPackage}, then its
* Class instance. Otherwise <code>null</code>.
* @throws ELException if the class is abstract or is an interface, or
* not public.
*/
public
Class<?>
resolveClass(
String name) {
String className =
classNameMap.
get(
name);
if (
className != null) {
return
resolveClassFor(
className);
}
for (
String packageName:
packages) {
String fullClassName =
packageName + "." +
name;
Class<?>
c =
resolveClassFor(
fullClassName);
if (
c != null) {
classNameMap.
put(
name,
fullClassName);
return
c;
}
}
return null;
}
/**
* Resolve a static field or method name.
*
* @param name The name of the member(without package and class name)
* to be resolved.
* @return If the field or method has been imported previously, with
* {@link #importStatic}, then the class object representing the class that
* declares the static field or method.
* Otherwise <code>null</code>.
* @throws ELException if the class is not public, or is abstract or
* is an interface.
*/
public
Class<?>
resolveStatic(
String name) {
String className =
staticNameMap.
get(
name);
if (
className != null) {
Class<?>
c =
resolveClassFor(
className);
if (
c != null) {
return
c;
}
}
return null;
}
private
Class<?>
resolveClassFor(
String className) {
Class<?>
c =
classMap.
get(
className);
if (
c != null) {
return
c;
}
c =
getClassFor(
className);
if (
c != null) {
checkModifiers(
c.
getModifiers());
classMap.
put(
className,
c);
}
return
c;
}
private
Class<?>
getClassFor(
String className) {
if (!
notAClass.
contains(
className)) {
try {
return
Class.
forName(
className, false,
getClass().
getClassLoader());
} catch (
ClassNotFoundException ex) {
notAClass.
add(
className);
}
}
return null;
}
private void
checkModifiers(int
modifiers) {
if (
Modifier.
isAbstract(
modifiers) ||
Modifier.
isInterface(
modifiers)
|| !
Modifier.
isPublic((
modifiers))) {
throw new
ELException("Imported class must be public, and cannot be abstract or an interface");
}
}
}