org.springframework.mail.javamail.ConfigurableMimeFileTypeMap Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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.mail.javamail;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import javax.activation.FileTypeMap;
import javax.activation.MimetypesFileTypeMap;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.lang.Nullable;
/**
* Spring-configurable {@code FileTypeMap} implementation that will read
* MIME type to file extension mappings from a standard JavaMail MIME type
* mapping file, using a standard {@code MimetypesFileTypeMap} underneath.
*
* The mapping file should be in the following format, as specified by the
* Java Activation Framework:
*
*
* # map text/html to .htm and .html files
* text/html html htm HTML HTM
*
* Lines starting with {@code #} are treated as comments and are ignored. All
* other lines are treated as mappings. Each mapping line should contain the MIME
* type as the first entry and then each file extension to map to that MIME type
* as subsequent entries. Each entry is separated by spaces or tabs.
*
* By default, the mappings in the {@code mime.types} file located in the
* same package as this class are used, which cover many common file extensions
* (in contrast to the out-of-the-box mappings in {@code activation.jar}).
* This can be overridden using the {@code mappingLocation} property.
*
*
Additional mappings can be added via the {@code mappings} bean property,
* as lines that follow the {@code mime.types} file format.
*
* @author Rob Harrop
* @author Juergen Hoeller
* @since 1.2
* @see #setMappingLocation
* @see #setMappings
* @see javax.activation.MimetypesFileTypeMap
*/
public class ConfigurableMimeFileTypeMap extends FileTypeMap implements InitializingBean {
/**
* The {@code Resource} to load the mapping file from.
*/
private Resource mappingLocation = new ClassPathResource("mime.types", getClass());
/**
* Used to configure additional mappings.
*/
@Nullable
private String[] mappings;
/**
* The delegate FileTypeMap, compiled from the mappings in the mapping file
* and the entries in the {@code mappings} property.
*/
@Nullable
private FileTypeMap fileTypeMap;
/**
* Specify the {@code Resource} from which mappings are loaded.
*
Needs to follow the {@code mime.types} file format, as specified
* by the Java Activation Framework, containing lines such as:
* {@code text/html html htm HTML HTM}
*/
public void setMappingLocation(Resource mappingLocation) {
this.mappingLocation = mappingLocation;
}
/**
* Specify additional MIME type mappings as lines that follow the
* {@code mime.types} file format, as specified by the
* Java Activation Framework. For example:
* {@code text/html html htm HTML HTM}
*/
public void setMappings(String... mappings) {
this.mappings = mappings;
}
/**
* Creates the final merged mapping set.
*/
@Override
public void afterPropertiesSet() {
getFileTypeMap();
}
/**
* Return the delegate FileTypeMap, compiled from the mappings in the mapping file
* and the entries in the {@code mappings} property.
* @see #setMappingLocation
* @see #setMappings
* @see #createFileTypeMap
*/
protected final FileTypeMap getFileTypeMap() {
if (this.fileTypeMap == null) {
try {
this.fileTypeMap = createFileTypeMap(this.mappingLocation, this.mappings);
}
catch (IOException ex) {
throw new IllegalStateException(
"Could not load specified MIME type mapping file: " + this.mappingLocation, ex);
}
}
return this.fileTypeMap;
}
/**
* Compile a {@link FileTypeMap} from the mappings in the given mapping file
* and the given mapping entries.
*
The default implementation creates an Activation Framework {@link MimetypesFileTypeMap},
* passing in an InputStream from the mapping resource (if any) and registering
* the mapping lines programmatically.
* @param mappingLocation a {@code mime.types} mapping resource (can be {@code null})
* @param mappings an array of MIME type mapping lines (can be {@code null})
* @return the compiled FileTypeMap
* @throws IOException if resource access failed
* @see javax.activation.MimetypesFileTypeMap#MimetypesFileTypeMap(java.io.InputStream)
* @see javax.activation.MimetypesFileTypeMap#addMimeTypes(String)
*/
protected FileTypeMap createFileTypeMap(@Nullable Resource mappingLocation, @Nullable String[] mappings) throws IOException {
MimetypesFileTypeMap fileTypeMap = null;
if (mappingLocation != null) {
InputStream is = mappingLocation.getInputStream();
try {
fileTypeMap = new MimetypesFileTypeMap(is);
}
finally {
is.close();
}
}
else {
fileTypeMap = new MimetypesFileTypeMap();
}
if (mappings != null) {
for (String mapping : mappings) {
fileTypeMap.addMimeTypes(mapping);
}
}
return fileTypeMap;
}
/**
* Delegates to the underlying FileTypeMap.
* @see #getFileTypeMap()
*/
@Override
public String getContentType(File file) {
return getFileTypeMap().getContentType(file);
}
/**
* Delegates to the underlying FileTypeMap.
* @see #getFileTypeMap()
*/
@Override
public String getContentType(String fileName) {
return getFileTypeMap().getContentType(fileName);
}
}