org.apache.juneau.internal.ClassUtils Maven / Gradle / Ivy
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// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance *
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// * *
// * http://www.apache.org/licenses/LICENSE-2.0 *
// * *
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package org.apache.juneau.internal;
import java.lang.reflect.*;
import java.util.function.*;
import org.apache.juneau.*;
import org.apache.juneau.reflect.*;
/**
* Class-related utility methods.
*
* See Also:
*
*/
public final class ClassUtils {
/**
* Predicate check to filter out void classes.
*/
public static final Predicate> NOT_VOID = ClassUtils::isNotVoid;
/**
* Returns the class types for the specified arguments.
*
* @param args The objects we're getting the classes of.
* @return The classes of the arguments.
*/
public static Class[] getClasses(Object...args) {
Class[] pt = new Class[args.length];
for (int i = 0; i < args.length; i++)
pt[i] = args[i] == null ? null : args[i].getClass();
return pt;
}
/**
* Matches arguments to a list of parameter types.
*
*
* Extra parameters are ignored.
*
Missing parameters are left null.
*
* @param paramTypes The parameter types.
* @param args The arguments to match to the parameter types.
* @return
* An array of parameters.
*/
public static Object[] getMatchingArgs(Class[] paramTypes, Object... args) {
boolean needsShuffle = paramTypes.length != args.length;
if (! needsShuffle) {
for (int i = 0; i < paramTypes.length; i++) {
if (! paramTypes[i].isInstance(args[i]))
needsShuffle = true;
}
}
if (! needsShuffle)
return args;
Object[] params = new Object[paramTypes.length];
for (int i = 0; i < paramTypes.length; i++) {
ClassInfo pt = ClassInfo.of(paramTypes[i]).getWrapperInfoIfPrimitive();
for (Object arg : args) {
if (arg != null && pt.isParentOf(arg.getClass())) {
params[i] = arg;
break;
}
}
}
return params;
}
/**
* Attempts to call x.setAccessible(true ) and quietly ignores security exceptions.
*
* @param x The constructor.
* @return true if call was successful.
*/
public static boolean setAccessible(Constructor x) {
try {
if (x != null)
x.setAccessible(true);
return true;
} catch (SecurityException e) {
return false;
}
}
/**
* Attempts to call x.setAccessible(true ) and quietly ignores security exceptions.
*
* @param x The method.
* @return true if call was successful.
*/
public static boolean setAccessible(Method x) {
try {
if (x != null)
x.setAccessible(true);
return true;
} catch (SecurityException e) {
return false;
}
}
/**
* Attempts to call x.setAccessible(true ) and quietly ignores security exceptions.
*
* @param x The field.
* @return true if call was successful.
*/
public static boolean setAccessible(Field x) {
try {
if (x != null)
x.setAccessible(true);
return true;
} catch (SecurityException e) {
return false;
}
}
/**
* Returns the specified type as a Class .
*
*
* If it's already a Class , it just does a cast.
*
If it's a ParameterizedType , it returns the raw type.
*
* @param t The type to convert.
* @return The type converted to a Class , or null if it could not be converted.
*/
public static Class toClass(Type t) {
if (t instanceof Class)
return (Class)t;
if (t instanceof ParameterizedType) {
ParameterizedType pt = (ParameterizedType)t;
// The raw type should always be a class (right?)
return (Class)pt.getRawType();
}
return null;
}
/**
* Returns the fully-qualified class name for the specified object.
*
* @param value The object to get the class name for.
* @return The name of the class or null if the value was null.
*/
public static String className(Object value) {
return value == null ? null : value instanceof Class ? ((Class)value).getName() : value.getClass().getName();
}
/**
* Returns the simple class name for the specified object.
*
* @param value The object to get the class name for.
* @return The name of the class or null if the value was null.
*/
public static String simpleClassName(Object value) {
if (value == null)
return null;
if (value instanceof ClassInfo)
return ((ClassInfo)value).getSimpleName();
if (value instanceof ClassMeta)
return ((ClassMeta)value).getSimpleName();
if (value instanceof Class)
return ((Class)value).getSimpleName();
return value.getClass().getSimpleName();
}
/**
* Returns true if the specific class is null or void .class "Void .
*
* @param c The class to check.
* @return true if the specific class is null or void .class "Void .
*/
@SuppressWarnings("rawtypes")
public static boolean isVoid(Class c) {
return (c == null || c == void.class || c == Void.class || c.getSimpleName().equalsIgnoreCase("void"));
}
/**
* Returns false if the specific class is null or void .class "Void .
*
* @param c The class to check.
* @return false if the specific class is null or void .class "Void .
*/
@SuppressWarnings("rawtypes")
public static boolean isNotVoid(Class c) {
return ! isVoid(c);
}
}