org.apache.sshd.common.util.IgnoringEmptyMap Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
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/*
* 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.util.Collection;
import java.util.Collections;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
/**
* A dummy map that ignores all {@code put/remove} calls
*
* @param Key type
* @param Value type
* @author Apache MINA SSHD Project
*/
public class IgnoringEmptyMap implements Map {
@SuppressWarnings("rawtypes")
private static final IgnoringEmptyMap INSTANCE = new IgnoringEmptyMap();
public IgnoringEmptyMap() {
super();
}
@Override
public int size() {
return 0;
}
@Override
public boolean isEmpty() {
return true;
}
@Override
public boolean containsValue(Object value) {
Objects.requireNonNull(value, "No value provided");
return false;
}
@Override
public boolean containsKey(Object key) {
Objects.requireNonNull(key, "No key provided");
return false;
}
@Override
public V get(Object key) {
Objects.requireNonNull(key, "No key provided");
return null;
}
@Override
public V put(K key, V value) {
Objects.requireNonNull(key, "No key provided");
Objects.requireNonNull(value, "No value provided");
return null;
}
@Override
public V remove(Object key) {
Objects.requireNonNull(key, "No key provided");
return null;
}
@Override
public void putAll(Map extends K, ? extends V> m) {
// ignored
}
@Override
public void clear() {
// ignored
}
@Override
public Set keySet() {
return Collections.emptySet();
}
@Override
public Collection values() {
return Collections.emptyList();
}
@Override
public boolean equals(Object o) {
return o instanceof IgnoringEmptyMap, ?>;
}
@Override
public int hashCode() {
return 0;
}
@Override
public String toString() {
return "{}";
}
@Override
public Set> entrySet() {
return Collections.emptySet();
}
@SuppressWarnings("unchecked")
public static IgnoringEmptyMap getInstance() {
return INSTANCE;
}
}