Java example source code file (MimeTypeRange.java)

This example Java source code file (MimeTypeRange.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

all, arraylist, collection, error, hashmap, illegalargumentexception, list, mimetypeparseexception, mimetyperange, parseexception, string, stringbuilder, stringcutter, text, util

The MimeTypeRange.java Java example source code

/*
 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.tools.internal.xjc.util;

import java.text.ParseException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.activation.MimeType;
import javax.activation.MimeTypeParseException;

/**
 * @author Kohsuke Kawaguchi
 */
public class MimeTypeRange {
    public final String majorType;
    public final String subType;

    public final Map<String,String> parameters = new HashMap();

    /**
     * Each media-range MAY be followed by one or more accept-params,
     * beginning with the "q" parameter for indicating a relative quality
     * factor. The first "q" parameter (if any) separates the media-range
     * parameter(s) from the accept-params. Quality factors allow the user
     * or user agent to indicate the relative degree of preference for that
     * media-range, using the qvalue scale from 0 to 1 (section 3.9). The
     * default value is q=1.
     */
    public final float q;

    // accept-extension is not implemented

    public static List<MimeTypeRange> parseRanges(String s) throws ParseException {
        StringCutter cutter = new StringCutter(s,true);
        List<MimeTypeRange> r = new ArrayList();
        while(cutter.length()>0) {
            r.add(new MimeTypeRange(cutter));
        }
        return r;
    }

    public MimeTypeRange(String s) throws ParseException {
        this(new StringCutter(s,true));
    }

    /**
     * Used only to produce the static constants within this class.
     */
    private static MimeTypeRange create(String s) {
        try {
            return new MimeTypeRange(s);
        } catch (ParseException e) {
            // we only use this method for known inputs
            throw new Error(e);
        }
    }

    /**
     * @param cutter
     *      A string like "text/html; charset=utf-8;
     */
    private MimeTypeRange(StringCutter cutter) throws ParseException {
        majorType = cutter.until("/");
        cutter.next("/");
        subType = cutter.until("[;,]");

        float q = 1.0f;

        while(cutter.length()>0) {
            String sep = cutter.next("[;,]");
            if(sep.equals(","))
                break;

            String key = cutter.until("=");
            cutter.next("=");
            String value;
            char ch = cutter.peek();
            if(ch=='"') {
                // quoted
                cutter.next("\"");
                value = cutter.until("\"");
                cutter.next("\"");
            } else {
                value = cutter.until("[;,]");
            }

            if(key.equals("q")) {
                q = Float.parseFloat(value);
            } else {
                parameters.put(key,value);
            }
        }

        this.q = q;
    }

    public MimeType toMimeType() throws MimeTypeParseException {
        // due to the additional error check done in the MimeType class,
        // an error at this point is possible
        return new MimeType(toString());
    }

    public String toString() {
        StringBuilder sb = new StringBuilder(majorType+'/'+subType);
        if(q!=1)
            sb.append("; q=").append(q);

        for( Map.Entry<String,String> p : parameters.entrySet() ) {
            // I'm too lazy to quote the value
            sb.append("; ").append(p.getKey()).append('=').append(p.getValue());
        }
        return sb.toString();
    }

    public static final MimeTypeRange ALL = create("*/*");

    /**
     * Creates a range by merging all the given types.
     */
    public static MimeTypeRange merge( Collection<MimeTypeRange> types ) {
        if(types.size()==0)     throw new IllegalArgumentException();
        if(types.size()==1)     return types.iterator().next();

        String majorType=null;
        for (MimeTypeRange mt : types) {
            if(majorType==null)     majorType = mt.majorType;
            if(!majorType.equals(mt.majorType))
                return ALL;
        }

        return create(majorType+"/*");
    }

    public static void main(String[] args) throws ParseException {
        for( MimeTypeRange m : parseRanges(args[0]))
            System.out.println(m.toString());
    }
}