javax.ws.rs.core.Variant Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* http://www.opensource.org/licenses/cddl1.php
* See the License for the specific language governing
* permissions and limitations under the License.
*/
/*
* Variant.java
*
* Created on September 27, 2007, 3:12 PM
*
*/
package javax.ws.rs.core;
import java.io.StringWriter;
import java.util.List;
import java.util.Locale;
import javax.ws.rs.ext.RuntimeDelegate;
/**
* Abstraction for a resource representation variant.
*/
public class Variant {
private Locale language;
private MediaType mediaType;
private String encoding;
/**
* Create a new instance of Variant
* @param mediaType the media type of the variant - may be null
* @param language the language of the variant - may be null
* @param encoding the content encoding of the variant - may be null
* @throws java.lang.IllegalArgumentException if all three parameters are
* null
*/
public Variant(MediaType mediaType, Locale language, String encoding) {
if (mediaType==null && language==null && encoding==null)
throw new IllegalArgumentException("mediaType, language, encoding all null");
this.encoding = encoding;
this.language = language;
this.mediaType = mediaType;
}
/**
* Get the language of the variant
* @return the language or null if none set
*/
public Locale getLanguage() {
return language;
}
/**
* Get the media type of the variant
* @return the media type or null if none set
*/
public MediaType getMediaType() {
return mediaType;
}
/**
* Get the encoding of the variant
* @return the encoding or null if none set
*/
public String getEncoding() {
return encoding;
}
/**
* Create a {@link VariantListBuilder} initialized with a set of supported
* media types.
* @param mediaTypes the available mediaTypes. If specific charsets
* are supported they should be included as parameters of the respective
* media type.
* @return the initailized builder
* @throws java.lang.IllegalArgumentException if mediaTypes is null or
* contains no elements.
*/
public static VariantListBuilder mediaTypes(MediaType... mediaTypes) {
VariantListBuilder b = VariantListBuilder.newInstance();
b.mediaTypes(mediaTypes);
return b;
}
/**
* Create a {@link VariantListBuilder} initialized with a set of supported
* languages.
* @param languages the available languages.
* @return the initailized builder
* @throws java.lang.IllegalArgumentException if languages is null or
* contains no elements.
*/
public static VariantListBuilder languages(Locale... languages) {
VariantListBuilder b = VariantListBuilder.newInstance();
b.languages(languages);
return b;
}
/**
* Create a {@link VariantListBuilder} initialized with a set of supported
* encodings.
* @param encodings the available encodings.
* @return the initailized builder
* @throws java.lang.IllegalArgumentException if encodings is null or
* contains no elements.
*/
public static VariantListBuilder encodings(String... encodings) {
VariantListBuilder b = VariantListBuilder.newInstance();
b.encodings(encodings);
return b;
}
/**
* Generate hash code from variant properties.
* @return the hash code
*/
@Override
public int hashCode() {
int hash = 7;
hash = 29 * hash + (this.language != null ? this.language.hashCode() : 0);
hash = 29 * hash + (this.mediaType != null ? this.mediaType.hashCode() : 0);
hash = 29 * hash + (this.encoding != null ? this.encoding.hashCode() : 0);
return hash;
}
/**
* Compares obj to this variant to see if they are the same
* considering all property values.
* @param obj the object to compare to
* @return true if the two variants are the same, false otherwise.
*/
@Override
public boolean equals(Object obj) {
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
final Variant other = (Variant) obj;
if (this.language != other.language && (this.language == null || !this.language.equals(other.language))) {
return false;
}
if (this.mediaType != other.mediaType && (this.mediaType == null || !this.mediaType.equals(other.mediaType))) {
return false;
}
if (this.encoding != other.encoding && (this.encoding == null || !this.encoding.equals(other.encoding))) {
return false;
}
return true;
}
@Override
public String toString() {
StringWriter w = new StringWriter();
w.append("Variant[mediaType=");
w.append(mediaType==null ? "null" : mediaType.toString());
w.append(", language=");
w.append(language==null ? "null" : language.toString());
w.append(", encoding=");
w.append(encoding==null ? "null" : encoding);
w.append("]");
return w.toString();
}
/**
* A builder for a list of representation variants.
*/
public static abstract class VariantListBuilder {
/**
* Protected constructor, use the static newInstance
* method to obtain an instance.
*/
protected VariantListBuilder() {}
/**
* Create a new builder instance.
* @return a new Builder
*/
public static VariantListBuilder newInstance() {
VariantListBuilder b = RuntimeDelegate.getInstance().createVariantListBuilder();
return b;
}
/**
* Build a list of representation variants from the current state of
* the builder. After this method is called the builder is reset to
* an empty state.
* @return a list of representation variants
*/
public abstract List build();
/**
* Add the current combination of metadata to the list of supported variants,
* after this method is called the current combination of metadata is emptied.
* If more than one value is supplied for one or more of the variant properties
* then a variant will be generated for each possible combination. E.g.
* in the following list would have four members:
* List list = VariantListBuilder.newInstance().languages("en","fr")
* .encodings("zip", "identity").add().build()
*
* @return the updated builder
* @throws java.lang.IllegalStateException if there is not at least one
* mediaType, language or encoding set for the current variant.
*/
public abstract VariantListBuilder add();
/**
* Set the language[s] for this variant.
* @param languages the available languages
* @return the updated builder
*/
public abstract VariantListBuilder languages(Locale... languages);
/**
* Set the encoding[s] for this variant.
* @param encodings the available encodings
* @return the updated builder
*/
public abstract VariantListBuilder encodings(String... encodings);
/**
* Set the media type[s] for this variant.
* @param mediaTypes the available mediaTypes. If specific charsets
* are supported they should be included as parameters of the respective
* media type.
* @return the updated builder
*/
public abstract VariantListBuilder mediaTypes(MediaType... mediaTypes);
}
}