/*
* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.http.entity;
import java.io.Serializable;
import java.nio.charset.Charset;
import java.nio.charset.UnsupportedCharsetException;
import java.util.Locale;
import org.apache.http.Consts;
import org.apache.http.Header;
import org.apache.http.HeaderElement;
import org.apache.http.HttpEntity;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.annotation.Immutable;
import org.apache.http.message.BasicHeaderValueFormatter;
import org.apache.http.message.BasicHeaderValueParser;
import org.apache.http.message.ParserCursor;
import org.apache.http.util.Args;
import org.apache.http.util.CharArrayBuffer;
import org.apache.http.util.TextUtils;
/**
* Content type information consisting of a MIME type and an optional charset.
* <p/>
* This class makes no attempts to verify validity of the MIME type.
* The input parameters of the {@link #create(String, String)} method, however, may not
* contain characters <">, <;>, <,> reserved by the HTTP specification.
*
* @since 4.2
*/
@Immutable
public final class ContentType implements Serializable {
private static final long serialVersionUID = -7768694718232371896L;
// constants
public static final ContentType APPLICATION_ATOM_XML = create(
"application/atom+xml", Consts.ISO_8859_1);
public static final ContentType APPLICATION_FORM_URLENCODED = create(
"application/x-www-form-urlencoded", Consts.ISO_8859_1);
public static final ContentType APPLICATION_JSON = create(
"application/json", Consts.UTF_8);
public static final ContentType APPLICATION_OCTET_STREAM = create(
"application/octet-stream", (Charset) null);
public static final ContentType APPLICATION_SVG_XML = create(
"application/svg+xml", Consts.ISO_8859_1);
public static final ContentType APPLICATION_XHTML_XML = create(
"application/xhtml+xml", Consts.ISO_8859_1);
public static final ContentType APPLICATION_XML = create(
"application/xml", Consts.ISO_8859_1);
public static final ContentType MULTIPART_FORM_DATA = create(
"multipart/form-data", Consts.ISO_8859_1);
public static final ContentType TEXT_HTML = create(
"text/html", Consts.ISO_8859_1);
public static final ContentType TEXT_PLAIN = create(
"text/plain", Consts.ISO_8859_1);
public static final ContentType TEXT_XML = create(
"text/xml", Consts.ISO_8859_1);
public static final ContentType WILDCARD = create(
"*/*", (Charset) null);
// defaults
public static final ContentType DEFAULT_TEXT = TEXT_PLAIN;
public static final ContentType DEFAULT_BINARY = APPLICATION_OCTET_STREAM;
private final String mimeType;
private final Charset charset;
private final NameValuePair[] params;
ContentType(
final String mimeType,
final Charset charset) {
this.mimeType = mimeType;
this.charset = charset;
this.params = null;
}
ContentType(
final String mimeType,
final Charset charset,
final NameValuePair[] params) {
this.mimeType = mimeType;
this.charset = charset;
this.params = params;
}
public String getMimeType() {
return this.mimeType;
}
public Charset getCharset() {
return this.charset;
}
/**
* @since 4.3
*/
public String getParameter(final String name) {
Args.notEmpty(name, "Parameter name");
if (this.params == null) {
return null;
}
for (final NameValuePair param: this.params) {
if (param.getName().equalsIgnoreCase(name)) {
return param.getValue();
}
}
return null;
}
/**
* Generates textual representation of this content type which can be used as the value
* of a <code>Content-Type</code> header.
*/
@Override
public String toString() {
final CharArrayBuffer buf = new CharArrayBuffer(64);
buf.append(this.mimeType);
if (this.params != null) {
buf.append("; ");
BasicHeaderValueFormatter.INSTANCE.formatParameters(buf, this.params, false);
} else if (this.charset != null) {
buf.append("; charset=");
buf.append(this.charset.name());
}
return buf.toString();
}
private static boolean valid(final String s) {
for (int i = 0; i < s.length(); i++) {
final char ch = s.charAt(i);
if (ch == '"' || ch == ',' || ch == ';') {
return false;
}
}
return true;
}
/**
* Creates a new instance of {@link ContentType}.
*
* @param mimeType MIME type. It may not be <code>null</code> or empty. It may not contain
* characters <">, <;>, <,> reserved by the HTTP specification.
* @param charset charset.
* @return content type
*/
public static ContentType create(final String mimeType, final Charset charset) {
final String type = Args.notBlank(mimeType, "MIME type").toLowerCase(Locale.ROOT);
Args.check(valid(type), "MIME type may not contain reserved characters");
return new ContentType(type, charset);
}
/**
* Creates a new instance of {@link ContentType} without a charset.
*
* @param mimeType MIME type. It may not be <code>null</code> or empty. It may not contain
* characters <">, <;>, <,> reserved by the HTTP specification.
* @return content type
*/
public static ContentType create(final String mimeType) {
return new ContentType(mimeType, (Charset) null);
}
/**
* Creates a new instance of {@link ContentType}.
*
* @param mimeType MIME type. It may not be <code>null</code> or empty. It may not contain
* characters <">, <;>, <,> reserved by the HTTP specification.
* @param charset charset. It may not contain characters <">, <;>, <,> reserved by the HTTP
* specification. This parameter is optional.
* @return content type
* @throws UnsupportedCharsetException Thrown when the named charset is not available in
* this instance of the Java virtual machine
*/
public static ContentType create(
final String mimeType, final String charset) throws UnsupportedCharsetException {
return create(mimeType, !TextUtils.isBlank(charset) ? Charset.forName(charset) : null);
}
private static ContentType create(final HeaderElement helem, final boolean strict) {
final String mimeType = helem.getName();
final NameValuePair[] params = helem.getParameters();
Charset charset = null;
for (final NameValuePair param: params) {
if (param.getName().equalsIgnoreCase("charset")) {
final String s = param.getValue();
if (!TextUtils.isBlank(s)) {
try {
charset = Charset.forName(s);
} catch (UnsupportedCharsetException ex) {
if (strict) {
throw ex;
}
}
}
break;
}
}
return new ContentType(mimeType, charset, params != null && params.length > 0 ? params : null);
}
/**
* Parses textual representation of <code>Content-Type</code> value.
*
* @param s text
* @return content type
* @throws ParseException if the given text does not represent a valid
* <code>Content-Type</code> value.
* @throws UnsupportedCharsetException Thrown when the named charset is not available in
* this instance of the Java virtual machine
*/
public static ContentType parse(
final String s) throws ParseException, UnsupportedCharsetException {
Args.notNull(s, "Content type");
final CharArrayBuffer buf = new CharArrayBuffer(s.length());
buf.append(s);
final ParserCursor cursor = new ParserCursor(0, s.length());
final HeaderElement[] elements = BasicHeaderValueParser.INSTANCE.parseElements(buf, cursor);
if (elements.length > 0) {
return create(elements[0], true);
} else {
throw new ParseException("Invalid content type: " + s);
}
}
/**
* Extracts <code>Content-Type</code> value from {@link HttpEntity} exactly as
* specified by the <code>Content-Type</code> header of the entity. Returns <code>null</code>
* if not specified.
*
* @param entity HTTP entity
* @return content type
* @throws ParseException if the given text does not represent a valid
* <code>Content-Type</code> value.
* @throws UnsupportedCharsetException Thrown when the named charset is not available in
* this instance of the Java virtual machine
*/
public static ContentType get(
final HttpEntity entity) throws ParseException, UnsupportedCharsetException {
if (entity == null) {
return null;
}
final Header header = entity.getContentType();
if (header != null) {
final HeaderElement[] elements = header.getElements();
if (elements.length > 0) {
return create(elements[0], true);
}
}
return null;
}
/**
* Extracts <code>Content-Type</code> value from {@link HttpEntity}. Returns <code>null</code>
* if not specified or incorrect (could not be parsed)..
*
* @param entity HTTP entity
* @return content type
*
* @since 4.4
*
*/
public static ContentType getLenient(final HttpEntity entity) {
if (entity == null) {
return null;
}
final Header header = entity.getContentType();
if (header != null) {
try {
final HeaderElement[] elements = header.getElements();
if (elements.length > 0) {
return create(elements[0], false);
}
} catch (ParseException ex) {
return null;
}
}
return null;
}
/**
* Extracts <code>Content-Type</code> value from {@link HttpEntity} or returns the default value
* {@link #DEFAULT_TEXT} if not explicitly specified.
*
* @param entity HTTP entity
* @return content type
* @throws ParseException if the given text does not represent a valid
* <code>Content-Type</code> value.
* @throws UnsupportedCharsetException Thrown when the named charset is not available in
* this instance of the Java virtual machine
*/
public static ContentType getOrDefault(
final HttpEntity entity) throws ParseException, UnsupportedCharsetException {
final ContentType contentType = get(entity);
return contentType != null ? contentType : DEFAULT_TEXT;
}
/**
* Extracts <code>Content-Type</code> value from {@link HttpEntity} or returns the default value
* {@link #DEFAULT_TEXT} if not explicitly specified or incorrect (could not be parsed).
*
* @param entity HTTP entity
* @return content type
*
* @since 4.4
*/
public static ContentType getLenientOrDefault(
final HttpEntity entity) throws ParseException, UnsupportedCharsetException {
final ContentType contentType = get(entity);
return contentType != null ? contentType : DEFAULT_TEXT;
}
/**
* Creates a new instance with this MIME type and the given Charset.
*
* @param charset charset
* @return a new instance with this MIME type and the given Charset.
* @since 4.3
*/
public ContentType withCharset(final Charset charset) {
return create(this.getMimeType(), charset);
}
/**
* Creates a new instance with this MIME type and the given Charset name.
*
* @param charset name
* @return a new instance with this MIME type and the given Charset name.
* @throws UnsupportedCharsetException Thrown when the named charset is not available in
* this instance of the Java virtual machine
* @since 4.3
*/
public ContentType withCharset(final String charset) {
return create(this.getMimeType(), charset);
}
}