org.apache.sshd.common.util.ReflectionUtils Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.sshd.common.util;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.util.Collection;
import java.util.function.Function;
import java.util.function.Predicate;
/**
* @author Apache MINA SSHD Project
*/
public final class ReflectionUtils {
public static final Function FIELD_NAME_EXTRACTOR = f -> (f == null) ? null : f.getName();
private ReflectionUtils() {
throw new UnsupportedOperationException("No instance");
}
public static Collection getMatchingFields(Class clazz, Predicate acceptor) {
return GenericUtils.selectMatchingMembers(acceptor, clazz.getFields());
}
public static Collection getMatchingDeclaredFields(Class clazz, Predicate acceptor) {
return GenericUtils.selectMatchingMembers(acceptor, clazz.getDeclaredFields());
}
/**
* @deprecated The preferred method is
* {@link org.apache.sshd.common.util.threads.ThreadUtils#resolveDefaultClass(Class, String)}
* which checks all possible ClassLoaders.
* @param cl
* @param className
* @return
*/
@Deprecated
public static boolean isClassAvailable(ClassLoader cl, String className) {
try {
cl.loadClass(className);
return true;
} catch (Throwable ignored) {
return false;
}
}
public static Object newInstance(Class clazz) throws ReflectiveOperationException {
return newInstance(clazz, Object.class);
}
@SuppressWarnings("checkstyle:ThrowsCount")
public static T newInstance(Class clazz, Class castType) throws ReflectiveOperationException {
Constructor ctor = clazz.getDeclaredConstructor();
Object instance = ctor.newInstance();
return castType.cast(instance);
}
}