org.springframework.messaging.handler.CompositeMessageCondition Maven / Gradle / Ivy
/*
* Copyright 2002-2019 the original author or authors.
*
* Licensed 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
*
* https://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.springframework.messaging.handler;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;
import org.springframework.lang.Nullable;
import org.springframework.messaging.Message;
import org.springframework.util.Assert;
/**
* Composite {@link MessageCondition} that delegates to other message conditions.
*
* For {@link #combine} and {@link #compareTo} it is expected that the "other"
* composite contains the same number, type, and order of message conditions.
*
* @author Rossen Stoyanchev
* @since 5.2
*/
public class CompositeMessageCondition implements MessageCondition {
private final List> messageConditions;
public CompositeMessageCondition(MessageCondition... messageConditions) {
this(Arrays.asList(messageConditions));
}
private CompositeMessageCondition(List> messageConditions) {
Assert.notEmpty(messageConditions, "No message conditions");
this.messageConditions = messageConditions;
}
public List> getMessageConditions() {
return this.messageConditions;
}
@SuppressWarnings("unchecked")
public > T getCondition(Class messageConditionType) {
for (MessageCondition condition : this.messageConditions) {
if (messageConditionType.isAssignableFrom(condition.getClass())) {
return (T) condition;
}
}
throw new IllegalStateException("No condition of type: " + messageConditionType);
}
@Override
public CompositeMessageCondition combine(CompositeMessageCondition other) {
checkCompatible(other);
List> result = new ArrayList<>(this.messageConditions.size());
for (int i = 0; i < this.messageConditions.size(); i++) {
result.add(combine(getMessageConditions().get(i), other.getMessageConditions().get(i)));
}
return new CompositeMessageCondition(result);
}
@SuppressWarnings("unchecked")
private > T combine(MessageCondition first, MessageCondition second) {
return ((T) first).combine((T) second);
}
@Override
public CompositeMessageCondition getMatchingCondition(Message message) {
List> result = new ArrayList<>(this.messageConditions.size());
for (MessageCondition condition : this.messageConditions) {
MessageCondition matchingCondition = (MessageCondition) condition.getMatchingCondition(message);
if (matchingCondition == null) {
return null;
}
result.add(matchingCondition);
}
return new CompositeMessageCondition(result);
}
@Override
public int compareTo(CompositeMessageCondition other, Message message) {
checkCompatible(other);
List> otherConditions = other.getMessageConditions();
for (int i = 0; i < this.messageConditions.size(); i++) {
int result = compare (this.messageConditions.get(i), otherConditions.get(i), message);
if (result != 0) {
return result;
}
}
return 0;
}
@SuppressWarnings("unchecked")
private > int compare(
MessageCondition first, MessageCondition second, Message message) {
return ((T) first).compareTo((T) second, message);
}
private void checkCompatible(CompositeMessageCondition other) {
List> others = other.getMessageConditions();
for (int i = 0; i < this.messageConditions.size(); i++) {
if (i < others.size()) {
if (this.messageConditions.get(i).getClass().equals(others.get(i).getClass())) {
continue;
}
}
throw new IllegalArgumentException("Mismatched CompositeMessageCondition: " +
this.messageConditions + " vs " + others);
}
}
@Override
public boolean equals(@Nullable Object other) {
if (this == other) {
return true;
}
if (!(other instanceof CompositeMessageCondition)) {
return false;
}
CompositeMessageCondition otherComposite = (CompositeMessageCondition) other;
checkCompatible(otherComposite);
List> otherConditions = otherComposite.getMessageConditions();
for (int i = 0; i < this.messageConditions.size(); i++) {
if (!this.messageConditions.get(i).equals(otherConditions.get(i))) {
return false;
}
}
return true;
}
@Override
public int hashCode() {
int hashCode = 0;
for (MessageCondition condition : this.messageConditions) {
hashCode += condition.hashCode() * 31;
}
return hashCode;
}
@Override
public String toString() {
return this.messageConditions.stream().map(Object::toString).collect(Collectors.joining(",", "{", "}"));
}
}