io.bitsensor.plugins.shaded.org.springframework.messaging.support.NativeMessageHeaderAccessor Maven / Gradle / Ivy
/*
* Copyright 2002-2016 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
*
* 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 io.bitsensor.plugins.shaded.org.springframework.messaging.support;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import io.bitsensor.plugins.shaded.org.springframework.messaging.Message;
import io.bitsensor.plugins.shaded.org.springframework.util.Assert;
import io.bitsensor.plugins.shaded.org.springframework.util.CollectionUtils;
import io.bitsensor.plugins.shaded.org.springframework.util.LinkedMultiValueMap;
import io.bitsensor.plugins.shaded.org.springframework.util.MultiValueMap;
import io.bitsensor.plugins.shaded.org.springframework.util.ObjectUtils;
/**
* An extension of {@link MessageHeaderAccessor} that also stores and provides read/write
* access to message headers from an external source -- e.g. a Spring {@link Message}
* created to represent a STOMP message received from a STOMP client or message broker.
* Native message headers are kept in a {@code Map>} under the key
* {@link #NATIVE_HEADERS}.
*
* This class is not intended for direct use but is rather expected to be used
* indirectly through protocol-specific sub-classes such as
* {@link io.bitsensor.plugins.shaded.org.springframework.messaging.simp.stomp.StompHeaderAccessor StompHeaderAccessor}.
* Such sub-classes may provide factory methods to translate message headers from
* an external messaging source (e.g. STOMP) to Spring {@link Message} headers and
* reversely to translate Spring {@link Message} headers to a message to send to an
* external source.
*
* @author Rossen Stoyanchev
* @since 4.0
*/
public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
public static final String NATIVE_HEADERS = "nativeHeaders";
/**
* A protected constructor to create new headers.
*/
protected NativeMessageHeaderAccessor() {
this((Map>) null);
}
/**
* A protected constructor to create new headers.
* @param nativeHeaders native headers to create the message with (may be {@code null})
*/
protected NativeMessageHeaderAccessor(Map> nativeHeaders) {
if (!CollectionUtils.isEmpty(nativeHeaders)) {
setHeader(NATIVE_HEADERS, new LinkedMultiValueMap(nativeHeaders));
}
}
/**
* A protected constructor accepting the headers of an existing message to copy.
*/
protected NativeMessageHeaderAccessor(Message message) {
super(message);
if (message != null) {
@SuppressWarnings("unchecked")
Map> map = (Map>) getHeader(NATIVE_HEADERS);
if (map != null) {
// Force removal since setHeader checks for equality
removeHeader(NATIVE_HEADERS);
setHeader(NATIVE_HEADERS, new LinkedMultiValueMap(map));
}
}
}
@SuppressWarnings("unchecked")
private Map> getNativeHeaders() {
return (Map>) getHeader(NATIVE_HEADERS);
}
/**
* Return a copy of the native header values or an empty map.
*/
public Map> toNativeHeaderMap() {
Map> map = getNativeHeaders();
return (map != null ? new LinkedMultiValueMap(map) : Collections.>emptyMap());
}
@Override
public void setImmutable() {
if (isMutable()) {
Map> map = getNativeHeaders();
if (map != null) {
// Force removal since setHeader checks for equality
removeHeader(NATIVE_HEADERS);
setHeader(NATIVE_HEADERS, Collections.>unmodifiableMap(map));
}
super.setImmutable();
}
}
/**
* Whether the native header map contains the give header name.
*/
public boolean containsNativeHeader(String headerName) {
Map> map = getNativeHeaders();
return (map != null && map.containsKey(headerName));
}
/**
* @return all values for the specified native header or {@code null}.
*/
public List getNativeHeader(String headerName) {
Map> map = getNativeHeaders();
return (map != null ? map.get(headerName) : null);
}
/**
* @return the first value for the specified native header of {@code null}.
*/
public String getFirstNativeHeader(String headerName) {
Map> map = getNativeHeaders();
if (map != null) {
List values = map.get(headerName);
if (values != null) {
return values.get(0);
}
}
return null;
}
/**
* Set the specified native header value replacing existing values.
*/
public void setNativeHeader(String name, String value) {
Assert.state(isMutable(), "Already immutable");
Map> map = getNativeHeaders();
if (value == null) {
if (map != null && map.get(name) != null) {
setModified(true);
map.remove(name);
}
return;
}
if (map == null) {
map = new LinkedMultiValueMap(4);
setHeader(NATIVE_HEADERS, map);
}
List values = new LinkedList();
values.add(value);
if (!ObjectUtils.nullSafeEquals(values, getHeader(name))) {
setModified(true);
map.put(name, values);
}
}
/**
* Add the specified native header value to existing values.
*/
public void addNativeHeader(String name, String value) {
Assert.state(isMutable(), "Already immutable");
if (value == null) {
return;
}
Map> nativeHeaders = getNativeHeaders();
if (nativeHeaders == null) {
nativeHeaders = new LinkedMultiValueMap(4);
setHeader(NATIVE_HEADERS, nativeHeaders);
}
List values = nativeHeaders.get(name);
if (values == null) {
values = new LinkedList();
nativeHeaders.put(name, values);
}
values.add(value);
setModified(true);
}
public void addNativeHeaders(MultiValueMap headers) {
if (headers == null) {
return;
}
for (Map.Entry> headerEntry : headers.entrySet()) {
for (String value : headerEntry.getValue()) {
addNativeHeader(headerEntry.getKey(), value);
}
}
}
public List removeNativeHeader(String name) {
Assert.state(isMutable(), "Already immutable");
Map> nativeHeaders = getNativeHeaders();
if (nativeHeaders == null) {
return null;
}
return nativeHeaders.remove(name);
}
@SuppressWarnings("unchecked")
public static String getFirstNativeHeader(String headerName, Map headers) {
Map> map = (Map>) headers.get(NATIVE_HEADERS);
if (map != null) {
List values = map.get(headerName);
if (values != null) {
return values.get(0);
}
}
return null;
}
}