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/*
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*
* Copyright (c) 1997-2012 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
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*/
package org.glassfish.admin.amx.util;
import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.HashSet;
import java.util.Set;
/*
Used internally.
*/
final class ClassToClassMapping
{
final Class mSrc;
final Class mDest;
public ClassToClassMapping(Class src, Class dest)
{
mSrc = src;
mDest = dest;
}
}
/**
Provides a variety of useful utilities having to do with classes, types of
objects, etc.
*/
public final class ClassUtil
{
private ClassUtil()
{
// disallow instantiation
}
public static boolean classIsAccessible(String name)
{
boolean accessible = false;
try
{
accessible = getClassFromName(name) != null;
}
catch (ClassNotFoundException e)
{
}
return (accessible);
}
public static boolean sigsEqual(
final Class[] sig1,
final Class[] sig2)
{
boolean equal = sig1.length == sig2.length;
if (equal)
{
for (int i = 0; i < sig1.length; ++i)
{
if (sig1[i] != sig2[i])
{
equal = false;
break;
}
}
}
return (equal);
}
/**
Test whether an Object is an array
@param o object to test
@return true if the object is an array, false otherwise.
*/
public static boolean objectIsArray(Object o)
{
return (classIsArray(o.getClass()));
}
/**
Test whether a Class is an array
@param theClass class to test
@return true if the class is an array, false otherwise.
*/
public static boolean classIsArray(Class theClass)
{
return (classnameIsArray(theClass.getName()));
}
/**
Test whether an Object is an array of primitive types
@param o object to test
@return true if the object is an array, false otherwise.
*/
public static boolean objectIsPrimitiveArray(Object o)
{
return (getPrimitiveArrayTypeCode(o.getClass()) != 0);
}
/**
Test whether a classname is an array
@param classname classname string
@return true if the object is an array, false otherwise.
*/
public static boolean classnameIsArray(String classname)
{
return (classname.startsWith("["));
}
/**
Strip the package name.
@param classname classname string
@return the classname, without its package
*/
public static String stripPackageName(String classname)
{
final int lastDot = classname.lastIndexOf(".");
if (lastDot < 0)
{
return (classname);
}
return (classname.substring(lastDot + 1, classname.length()));
}
/**
Test whether a classname is a primitive array
@param classname classname string
@return true if the object is a primitive array, false otherwise.
*/
public static boolean classnameIsPrimitiveArray(String classname)
{
return (getPrimitiveArrayTypeCode(classname) != 0);
}
/**
Return the primitive element type code for an array of primitive types.
Same as getPrimitiveArrayTypeCode( theClass.getName() )
@param theClass the Class object
@return the element type code; otherwise (char)0
*/
public static char getPrimitiveArrayTypeCode(Class theClass)
{
char typeCode = 0;
if (classIsArray(theClass))
{
typeCode = getPrimitiveArrayTypeCode(theClass.getName());
}
return (typeCode);
}
/**
Return the primitive element type code for an array of primitive types.
@param classname classname string
@return the element type code; otherwise (char)0
*/
public static char getPrimitiveArrayTypeCode(String classname)
{
char typeCode = 0;
final int length = classname.length();
if (classnameIsArray(classname) &&
classname.charAt(length - 2) == '[')
{
typeCode = classname.charAt(length - 1);
switch (typeCode)
{
default:
typeCode = 0;
break;
case 'Z':
case 'B':
case 'C':
case 'S':
case 'I':
case 'J':
case 'F':
case 'D':
break;
}
}
return (typeCode);
}
/**
Get the classname for an array element.
@param classname classname string
@return the classname for the array element
*/
public static String getArrayMemberClassName(String classname)
{
String result;
if (!classnameIsArray(classname))
{
throw new IllegalArgumentException("not an array");
}
final int classnameLength = classname.length();
if (classnameIsPrimitiveArray(classname))
{
final char lastChar = classname.charAt(classnameLength - 1);
switch (lastChar)
{
default:
throw new RuntimeException("illegal primitive");
// a simple type
case 'Z':
result = "boolean";
break;
case 'B':
result = "byte";
break;
case 'C':
result = "char";
break;
case 'S':
result = "short";
break;
case 'I':
result = "int";
break;
case 'J':
result = "long";
break;
case 'F':
result = "float";
break;
case 'D':
result = "double";
break;
}
}
else
{
// strip leading "[L" and trailing ";"
result = classname.substring(2, classnameLength - 1);
}
return (result);
}
/**
Class.forName does not work for primitive types, so we need to do it ourselves here.
*/
final static class ClassNameToClassMapping
{
String mName;
Class mClass;
ClassNameToClassMapping(String name, Class theClass)
{
mName = name;
mClass = theClass;
}
}
private static final ClassNameToClassMapping[] sPrimitiveNameToObjectClass =
new ClassNameToClassMapping[]
{
new ClassNameToClassMapping("int", int.class),
new ClassNameToClassMapping("long", long.class),
new ClassNameToClassMapping("short", short.class),
new ClassNameToClassMapping("byte", byte.class),
new ClassNameToClassMapping("boolean", boolean.class),
new ClassNameToClassMapping("float", float.class),
new ClassNameToClassMapping("double", double.class),
new ClassNameToClassMapping("char", char.class),
new ClassNameToClassMapping("void", void.class),
};
public static Class classForName(String name)
throws ClassNotFoundException
{
Class c;
try
{
c = Class.forName(name);
}
catch (ClassNotFoundException e)
{
c = Class.forName(name, true, Thread.currentThread().getContextClassLoader());
}
catch (NoClassDefFoundError e)
{
c = Class.forName(name, true, Thread.currentThread().getContextClassLoader());
}
return (c);
}
/**
Get a Class from a classname. Class.forName does not work for primitive types;
this methods returns the correct Class for any type.
@param classname classname string
@return the classname for the array element
*/
public static Class getClassFromName(final String classname)
throws ClassNotFoundException
{
Class theClass = null;
if (classname.startsWith("[L"))
{
// an array
theClass = classForName(classname);
}
else
{
final int numMappings = Array.getLength(sPrimitiveNameToObjectClass);
for (int i = 0; i < numMappings; ++i)
{
if (sPrimitiveNameToObjectClass[i].mName.equals(classname))
{
theClass = sPrimitiveNameToObjectClass[i].mClass;
break;
}
}
if (theClass == null)
{
theClass = classForName(classname);
}
}
return (theClass);
}
private static final ClassToClassMapping[] sPrimitiveClassToObjectClass =
new ClassToClassMapping[]
{
new ClassToClassMapping(boolean.class, Boolean.class),
new ClassToClassMapping(byte.class, Byte.class),
new ClassToClassMapping(char.class, Character.class),
new ClassToClassMapping(short.class, Short.class),
new ClassToClassMapping(int.class, Integer.class),
new ClassToClassMapping(long.class, Long.class),
new ClassToClassMapping(float.class, Float.class),
new ClassToClassMapping(double.class, Double.class),
};
/**
Map primitive class Classes to Object forms eg int.class to Integer.class
@param theClass the class to map
@return the corresponding Object class or the original Class if not a primitive.
*/
public static Class primitiveClassToObjectClass(final Class theClass)
{
Class result = theClass;
final int numMappings = Array.getLength(sPrimitiveClassToObjectClass);
for (int i = 0; i < numMappings; ++i)
{
final ClassToClassMapping mapping = sPrimitiveClassToObjectClass[i];
if (mapping.mSrc == theClass)
{
result = mapping.mDest;
break;
}
}
return (result);
}
/**
Map primitive class Classes to Object forms eg int.class to Integer.class
@param theClass the class to map
@return the corresponding Object class or the original Class if not a primitive.
*/
public static Class objectClassToPrimitiveClass(final Class theClass)
{
Class result = theClass;
final int numMappings = Array.getLength(sPrimitiveClassToObjectClass);
for (int i = 0; i < numMappings; ++i)
{
final ClassToClassMapping mapping = sPrimitiveClassToObjectClass[i];
if (mapping.mDest == theClass)
{
result = mapping.mSrc;
break;
}
}
return (result);
}
/**
Test whether a class is a primitive class.
@param theClass the class to test
@return true if it's a primitive class, false otherwise.
*/
public static boolean isPrimitiveClass(final Class theClass)
{
boolean isSimple = false;
final int numMappings = Array.getLength(sPrimitiveClassToObjectClass);
for (int i = 0; i < numMappings; ++i)
{
final ClassToClassMapping mapping = sPrimitiveClassToObjectClass[i];
if (mapping.mSrc.equals(theClass))
{
isSimple = true;
break;
}
}
return (isSimple);
}
/**
Convert a primitive class letter to its corresponding class name.
@param primitive the primitive character code
@return the corresponding classname
*/
public static String primitiveLetterToClassName(final char primitive)
{
String result;
// see JavaDoc on Class.getName()
switch (primitive)
{
case 'B':
result = "byte";
break;
case 'C':
result = "char";
break;
case 'D':
result = "double";
break;
case 'F':
result = "float";
break;
case 'I':
result = "int";
break;
case 'J':
result = "long";
break;
case 'S':
result = "short";
break;
case 'Z':
result = "boolean";
break;
default:
result = "" + primitive;
break;
}
return result;
}
/**
Return the corresponding classes for each element in an Object[]
If an element is null, then its corresponding Class will also be null.
@param args an array of objects.
@return an array of classes
*/
public static String[] getTypes(final Object[] args)
{
if (args == null)
{
return (null);
}
final int numArgs = Array.getLength(args);
final String[] types = new String[numArgs];
for (int i = 0; i < numArgs; ++i)
{
if (args[i] == null)
{
types[i] = null;
}
else
{
types[i] = args[i].getClass().getName();
}
}
return (types);
}
/**
Return the corresponding classes for each classname.
If an element is null, then its corresponding Class will also be null.
@param classnames an array of classnames.
@return an array of classes
*/
public static Class[] signatureFromClassnames(String[] classnames)
throws ClassNotFoundException
{
if (classnames == null)
{
return (null);
}
final Class[] signature = new Class[classnames.length];
for (int i = 0; i < signature.length; ++i)
{
signature[i] = getClassFromName(classnames[i]);
}
return (signature);
}
/**
Return the corresponding classes for each classname.
If an element is null, then its corresponding Class will also be null.
@param classes an array of classnames.
@return an array of classes
*/
public static String[] classnamesFromSignature(Class[] classes)
{
final String[] classnames = new String[classes.length];
for (int i = 0; i < classnames.length; ++i)
{
classnames[i] = classes[i].getName();
}
return (classnames);
}
/**
Get a "friendly" classname for a Class.
Calls getFriendlyClassname( theClass.getName() )
@param theClass the class for which the name should be gotten
@return the "friendly" name
*/
public static String getFriendlyClassname(Class theClass)
{
return (getFriendlyClassname(theClass.getName()));
}
/**
Convert a Java class name string into a more user friendly string. Examples:
java.lang.String => String
java.lang. => ;
[i => int[]
[Lfoo.bar.ClassName; => foo.bar.ClassName[]
The names returned correspond exactly to what a Java programmer would write, rather
than the internal JVM representation.
@param type
@return a friendlier string representing the type
*/
final static String javaLang = "java.lang.";
public static String getFriendlyClassname(String type)
{
String result = type;
if (type.startsWith("["))
{
// count how deep the array is
int depth = 0;
while (type.charAt(depth) == (int) '[')
{
++depth;
}
// strip all the '[' characters
result = type.substring(depth, type.length());
if (result.startsWith("L") && result.endsWith(";"))
{
result = result.substring(1, result.length() - 1);
}
else if (result.length() == 1)
{
// a simple type
switch (result.charAt(0))
{
case 'Z':
result = "boolean";
break;
case 'B':
result = "byte";
break;
case 'C':
result = "char";
break;
case 'S':
result = "short";
break;
case 'I':
result = "int";
break;
case 'J':
result = "long";
break;
case 'F':
result = "float";
break;
case 'D':
result = "double";
break;
default:
result = "unknown";
break;
}
}
StringBuilder sb = new StringBuilder(result);
for (int i = 0; i < depth; ++i)
{
sb.append("[]");
}
result = sb.toString();
}
if (result.startsWith(javaLang))
{
result = result.substring(javaLang.length(), result.length());
}
return (result);
}
/*
*/
public static int getArrayDimensions(final Class theClass)
{
final String classname = theClass.getName();
int dim = 0;
while (classname.charAt(dim) == '[')
{
++dim;
}
return (dim);
}
/*
*/
public static Class getArrayElementClass(final Class arrayClass)
{
final String arrayClassName = arrayClass.getName();
if (!classnameIsArray(arrayClassName))
{
throw new IllegalArgumentException("not an array");
}
String name = arrayClassName;
// strip leading "["
name = name.substring(1, name.length());
if (!name.startsWith("["))
{
// element is not an array
if (name.startsWith("L"))
{
// an Object class; strip leading "L" and trailing ";"
name = name.substring(1, name.length() - 1);
}
else if (name.length() == 1)
{
// may be a primitive type
name = primitiveLetterToClassName(name.charAt(0));
}
}
else
{
// element is an array; return it
}
Class theClass = null;
try
{
theClass = getClassFromName(name);
}
catch (ClassNotFoundException e)
{
assert (false);
}
return (theClass);
}
public static Class getInnerArrayElementClass(final Class arrayClass)
throws ClassNotFoundException
{
Class elementClass = arrayClass;
do
{
elementClass = getArrayElementClass(elementClass);
}
while (classIsArray(elementClass));
return (elementClass);
}
private static Object instantiateObject(final String theString)
throws Exception
{
Object result;
try
{
result = instantiateNumber(theString);
}
catch (NumberFormatException e)
{
result = theString;
}
return (result);
}
/**
Return true if caller signature is compatible with callee.
@param callee the signature of the method to be called
@param argsSignature the signature of the argument list
*/
public static boolean signaturesAreCompatible(final Class[] callee, final Class[] argsSignature)
{
boolean compatible = false;
if (callee.length == argsSignature.length)
{
compatible = true;
for (int i = 0; i < callee.length; ++i)
{
if (!callee[i].isAssignableFrom(argsSignature[i]))
{
compatible = false;
break;
}
}
}
return (compatible);
}
/**
Find all methods that match the name.
*/
public static Method findMethod(
final Class theClass,
final String methodName,
final Class[] sig)
{
Method m = null;
try
{
m = theClass.getMethod(methodName, sig);
}
catch (NoSuchMethodException e)
{
// ok, doesn't exist
}
return (m);
}
/**
Find all methods that match the name.
*/
public static Set findMethods(
final Method[] candidates,
final String methodName)
{
final Set s = new HashSet();
for (int methodIdx = 0; methodIdx < candidates.length; ++methodIdx)
{
final Method method = candidates[methodIdx];
if (method.getName().equals(methodName))
{
s.add(method);
}
}
return (s);
}
/**
Create a new object of the specified class using a constructor
that accepts the specified arguments.
@param theClass the Class of the desired Object
@param args the argument list for the constructor
*/
public static T instantiateObject(final Class theClass, final Object[] args)
throws Exception
{
final Class[] signature = new Class[args.length];
for (int i = 0; i < signature.length; ++i)
{
signature[i] = args[i].getClass();
}
Constructor constructor = null;
try
{
// this will fail if a constructor takes an interface;
// the code below will then find a compatible constructor
constructor = theClass.getConstructor(signature);
}
catch (NoSuchMethodException e)
{
final Constructor[] constructors = TypeCast.asArray(theClass.getConstructors());
int numMatches = 0;
for (int i = 0; i < constructors.length; ++i)
{
final Constructor tempConstructor = constructors[i];
final Class[] tempSignature = tempConstructor.getParameterTypes();
if (signaturesAreCompatible(tempSignature, signature))
{
++numMatches;
constructor = tempConstructor;
// keep going; there could be more than one valid match
}
}
// to succeed, there must be exactly one match
if (numMatches != 1)
{
throw e;
}
}
T result = null;
try
{
result = constructor.newInstance(args);
}
catch (java.lang.reflect.InvocationTargetException e)
{
// InvocationTargetException wraps the real cause
final Throwable cause = e.getCause();
if (cause instanceof Exception)
{
throw (Exception) cause;
}
else
{
// shouldn't happen, so we'll just rethrow it
throw e;
}
}
return (result);
}
/**
Create a new object of the specified class using a String constructor.
@param theClass the Class of the desired Object
@param theString the string for a String constructor
@return the resulting Object
*/
public static T instantiateObject(final Class theClass, final String theString)
throws Exception
{
final Class[] signature = new Class[]
{
String.class
};
final Constructor constructor = theClass.getConstructor(signature);
T result = null;
try
{
result = constructor.newInstance(new Object[]
{
theString
});
}
catch (java.lang.reflect.InvocationTargetException e)
{
// InvocationTargetException wraps the real cause
Throwable cause = e.getCause();
if (cause instanceof Exception)
{
throw (Exception) cause;
}
else
{
// shouldn't happen, so we'll just rethrow it
throw e;
}
}
return (result);
}
/**
Create a new number based on a String.
Don't get fancy here, simple precedence:
Integer, Long if no decimal point, use Long if won't fit in an Integer
Double if decimal point (for maximum precision)
@param theString String representation of the number
@return the resulting Object
*/
private static Object instantiateNumber(final String theString)
throws Exception
{
Object result;
if (theString.indexOf('.') >= 0)
{
result = instantiateObject(Double.class, theString);
}
else
{
try
{
result = instantiateObject(Integer.class, theString);
}
catch (NumberFormatException e)
{
// perhaps it wouldn't fit; try it as a long
result = instantiateObject(Long.class, theString);
}
}
return result;
}
/**
Given a Class and a String, create a new instance with a constructor that accept
a String. Primitive types are instantiated as their equivalent Object forms.
@param theClass the class from which an instance should be instantiated
@param theString the string to be supplied to the constructor
@return the resulting Object
*/
public static Object instantiateFromString(final Class theClass, final String theString)
throws Exception
{
Object result;
// char and Character do not have a String constructor, so we must special-case it
if (theClass == Object.class)
{
// special case, apply rules to create an object
result = instantiateObject(theString);
}
else if (theClass == Number.class)
{
// special case, apply rules to create a number
result = instantiateNumber(theString);
}
else if (theClass == Character.class || theClass == char.class)
{
if (theString.length() != 1)
{
throw new IllegalArgumentException("not a character: " + theString);
}
result = Character.valueOf(theString.charAt(0));
}
else
{
final Class objectClass = primitiveClassToObjectClass(theClass);
result = instantiateObject(objectClass, theString);
}
return result;
}
/**
Given a Class, create a new instance with an empty constructor.
Primitive types are instantiated as their equivalent Object forms.
Any value is acceptable in the newly created object.
@param inClass the class from which an instance should be instantiated
@return the resulting Object
*/
public static Object instantiateDefault(final Class inClass)
throws Exception
{
Object result;
final Class objectClass = primitiveClassToObjectClass(inClass);
if (Number.class.isAssignableFrom(objectClass))
{
result = instantiateFromString(objectClass, "0");
}
else if (objectClass == Boolean.class)
{
result = Boolean.TRUE;
}
else if (objectClass == Character.class)
{
result = Character.valueOf('X');
}
else if (classIsArray(objectClass))
{
result = Array.newInstance(objectClass, 0);
}
else if (objectClass == Object.class)
{
result = "anyObject";
}
else if (objectClass == String.class)
{
result = "";
}
else if (objectClass == java.net.URL.class)
{
result = new java.net.URL("http://www.sun.com");
}
else if (objectClass == java.net.URI.class)
{
result = new java.net.URI("http://www.sun.com");
}
else if (classIsArray(inClass))
{
final int dimensions = 3;
result = Array.newInstance(getInnerArrayElementClass(inClass), dimensions);
}
else
{
result = objectClass.newInstance();
//result = InstantiateFromString( objectClass, "0" );
}
return result;
}
final static String[] sJavaLangTypes =
{
"Character", "Boolean", "Byte", "Short", "Integer", "Long", "Float", "Double", "String", "Object"
};
final static int sNumBaseTypes = Array.getLength(sJavaLangTypes);
/**
Expand an abbreviated classname into its true java name.
Turn "Integer" into "java.lang.Integer", etc.
*/
public static String expandClassName(final String name)
{
String fullName = name;
final int numTypes = sNumBaseTypes;
for (int i = 0; i < numTypes; ++i)
{
if (name.equals(sJavaLangTypes[i]))
{
fullName = "java.lang." + name;
break;
}
}
if (fullName == name) // no match so far
{
if (name.equals("Number"))
{
fullName = "java.lang." + name;
}
else if (name.equals("BigDecimal") || name.equals("BigInteger"))
{
fullName = "java.math." + name;
}
else if (name.equals("URL") || name.equals("URI"))
{
fullName = "java.net." + name;
}
else if (name.equals("Date"))
{
fullName = "java.util." + name;
}
else if (name.equals("ObjectName"))
{
fullName = "javax.management." + name;
}
}
return fullName;
}
/**
Convert inner element to another type. Only works for arrays of Objects. Example:
convertArrayClass( "[[[LObject;", "Long" ) =>[[[LLong;
@param arrayClass
@param newInnerType the desired Class of the innermost element
*/
public static Class convertArrayClass(final Class arrayClass, final Class newInnerType)
throws ClassNotFoundException
{
final String arrayClassname = arrayClass.getName();
if (!arrayClassname.endsWith(";"))
{
throw new IllegalArgumentException("not an array of Object");
}
final int innerNameBegin = 1 + arrayClassname.indexOf("L");
final String newClassName = arrayClassname.substring(0, innerNameBegin) + newInnerType.getName() + ";";
final Class newClass = getClassFromName(newClassName);
return (newClass);
}
private static class MyClassLoader extends ClassLoader
{
MyClassLoader()
{
this(Thread.currentThread().getContextClassLoader());
}
MyClassLoader(ClassLoader cl)
{
super(cl);
}
@Override
public Package[] getPackages()
{
return (super.getPackages());
}
}
public static Package[] getPackages()
{
return AccessController.doPrivileged(new PrivilegedAction() {
@Override
public MyClassLoader run() {
return new MyClassLoader();
}
}).getPackages();
}
public static Package[] getPackages(final ClassLoader cl)
{
return AccessController.doPrivileged(new PrivilegedAction() {
@Override
public MyClassLoader run() {
return new MyClassLoader(cl);
}
}).getPackages();
}
/**
*/
public static Object getFieldValue(
final Class theInterface,
final String name)
{
Object value;
try
{
final Field field = theInterface.getField(name);
value = field.get(theInterface);
}
catch (Exception e)
{
value = null;
}
return value;
}
public static String stripPackagePrefix(final String classname)
{
final int index = classname.lastIndexOf(".");
String result = classname;
if (index > 0)
{
result = classname.substring(index + 1, classname.length());
}
return result;
}
;
public static String getPackagePrefix(final String classname)
{
final int index = classname.lastIndexOf(".");
String result = classname;
if (index > 0)
{
result = classname.substring(0, index);
}
return result;
}
;
}