org.opensaml.messaging.context.navigate.MessageLookup Maven / Gradle / Ivy
/*
* Licensed to the University Corporation for Advanced Internet Development,
* Inc. (UCAID) under one or more contributor license agreements. See the
* NOTICE file distributed with this work for additional information regarding
* copyright ownership. The UCAID 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.opensaml.messaging.context.navigate;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import net.shibboleth.utilities.java.support.logic.Constraint;
import org.opensaml.messaging.context.MessageContext;
/**
* A {@link ContextDataLookupFunction} that returns the message from a {@link MessageContext}.
*
* @param type of message
*/
public class MessageLookup implements ContextDataLookupFunction {
/** Child context type to look up. */
private final Class messageType;
/**
* Constructor.
*
* @param type message type to look up
*/
public MessageLookup(@Nonnull final Class type) {
messageType = Constraint.isNotNull(type, "Message type cannot be null");
}
/** {@inheritDoc} */
@Override
@Nullable public T apply(@Nullable final MessageContext input) {
if (input != null && messageType.isInstance(input.getMessage())) {
return (T) input.getMessage();
}
return null;
}
}