org.springframework.messaging.converter.DefaultContentTypeResolver Maven / Gradle / Ivy
/*
* Copyright 2002-2017 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 org.springframework.messaging.converter;
import org.springframework.lang.Nullable;
import org.springframework.messaging.MessageHeaders;
import org.springframework.util.MimeType;
/**
* A default {@link ContentTypeResolver} that checks the
* {@link MessageHeaders#CONTENT_TYPE} header or falls back to a default value.
*
* The header value is expected to be a {@link org.springframework.util.MimeType}
* or a {@code String} that can be parsed into a {@code MimeType}.
*
* @author Rossen Stoyanchev
* @since 4.0
*/
public class DefaultContentTypeResolver implements ContentTypeResolver {
@Nullable
private MimeType defaultMimeType;
/**
* Set the default MIME type to use when there is no
* {@link MessageHeaders#CONTENT_TYPE} header present.
*
This property does not have a default value.
*/
public void setDefaultMimeType(@Nullable MimeType defaultMimeType) {
this.defaultMimeType = defaultMimeType;
}
/**
* Return the default MIME type to use if no
* {@link MessageHeaders#CONTENT_TYPE} header is present.
*/
@Nullable
public MimeType getDefaultMimeType() {
return this.defaultMimeType;
}
@Override
@Nullable
public MimeType resolve(@Nullable MessageHeaders headers) {
if (headers == null || headers.get(MessageHeaders.CONTENT_TYPE) == null) {
return this.defaultMimeType;
}
Object value = headers.get(MessageHeaders.CONTENT_TYPE);
if (value == null) {
return null;
}
else if (value instanceof MimeType) {
return (MimeType) value;
}
else if (value instanceof String) {
return MimeType.valueOf((String) value);
}
else {
throw new IllegalArgumentException(
"Unknown type for contentType header value: " + value.getClass());
}
}
@Override
public String toString() {
return "DefaultContentTypeResolver[" + "defaultMimeType=" + this.defaultMimeType + "]";
}
}