/*
 * Copyright (c) 1996, 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
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 */

package sun.net.www;

import java.util.Iterator;

/* This is useful for the nightmare of parsing multi-part HTTP/RFC822 headers
 * sensibly:
 * From a String like: 'timeout=15, max=5'
 * create an array of Strings:
 * { {"timeout", "15"},
 *   {"max", "5"}
 * }
 * From one like: 'Basic Realm="FuzzFace" Foo="Biz Bar Baz"'
 * create one like (no quotes in literal):
 * { {"basic", null},
 *   {"realm", "FuzzFace"}
 *   {"foo", "Biz Bar Baz"}
 * }
 * keys are converted to lower case, vals are left as is....
 *
 * @author Dave Brown
 */


public class HeaderParser {

    /* table of key/val pairs */
    String raw;
    String[][] tab;
    int nkeys;
    int asize = 10; // initial size of array is 10

    public HeaderParser(String raw) {
        this.raw = raw;
        tab = new String[asize][2];
        parse();
    }

    private HeaderParser () {
    }

    
create a new HeaderParser from this, whose keys (and corresponding values) range from "start" to "end-1"
/** * create a new HeaderParser from this, whose keys (and corresponding values) * range from "start" to "end-1" */
public HeaderParser subsequence (int start, int end) { if (start == 0 && end == nkeys) { return this; } if (start < 0 || start >= end || end > nkeys) throw new IllegalArgumentException ("invalid start or end"); HeaderParser n = new HeaderParser (); n.tab = new String [asize][2]; n.asize = asize; System.arraycopy (tab, start, n.tab, 0, (end-start)); n.nkeys= (end-start); return n; } private void parse() { if (raw != null) { raw = raw.trim(); char[] ca = raw.toCharArray(); int beg = 0, end = 0, i = 0; boolean inKey = true; boolean inQuote = false; int len = ca.length; while (end < len) { char c = ca[end]; if ((c == '=') && !inQuote) { // end of a key tab[i][0] = new String(ca, beg, end-beg).toLowerCase(); inKey = false; end++; beg = end; } else if (c == '\"') { if (inQuote) { tab[i++][1]= new String(ca, beg, end-beg); inQuote=false; do { end++; } while (end < len && (ca[end] == ' ' || ca[end] == ',')); inKey=true; beg=end; } else { inQuote=true; end++; beg=end; } } else if (c == ' ' || c == ',') { // end key/val, of whatever we're in if (inQuote) { end++; continue; } else if (inKey) { tab[i++][0] = (new String(ca, beg, end-beg)).toLowerCase(); } else { tab[i++][1] = (new String(ca, beg, end-beg)); } while (end < len && (ca[end] == ' ' || ca[end] == ',')) { end++; } inKey = true; beg = end; } else { end++; } if (i == asize) { asize = asize * 2; String[][] ntab = new String[asize][2]; System.arraycopy (tab, 0, ntab, 0, tab.length); tab = ntab; } } // get last key/val, if any if (--end > beg) { if (!inKey) { if (ca[end] == '\"') { tab[i++][1] = (new String(ca, beg, end-beg)); } else { tab[i++][1] = (new String(ca, beg, end-beg+1)); } } else { tab[i++][0] = (new String(ca, beg, end-beg+1)).toLowerCase(); } } else if (end == beg) { if (!inKey) { if (ca[end] == '\"') { tab[i++][1] = String.valueOf(ca[end-1]); } else { tab[i++][1] = String.valueOf(ca[end]); } } else { tab[i++][0] = String.valueOf(ca[end]).toLowerCase(); } } nkeys=i; } } public String findKey(int i) { if (i < 0 || i > asize) return null; return tab[i][0]; } public String findValue(int i) { if (i < 0 || i > asize) return null; return tab[i][1]; } public String findValue(String key) { return findValue(key, null); } public String findValue(String k, String Default) { if (k == null) return Default; k = k.toLowerCase(); for (int i = 0; i < asize; ++i) { if (tab[i][0] == null) { return Default; } else if (k.equals(tab[i][0])) { return tab[i][1]; } } return Default; } class ParserIterator implements Iterator<String> { int index; boolean returnsValue; // or key ParserIterator (boolean returnValue) { returnsValue = returnValue; } public boolean hasNext () { return index<nkeys; } public String next () { return tab[index++][returnsValue?1:0]; } public void remove () { throw new UnsupportedOperationException ("remove not supported"); } } public Iterator<String> keys () { return new ParserIterator (false); } public Iterator<String> values () { return new ParserIterator (true); } public String toString () { Iterator<String> k = keys(); StringBuilder sb = new StringBuilder(); sb.append("{size=").append(asize).append(" nkeys=").append(nkeys) .append(' '); for (int i=0; k.hasNext(); i++) { String key = k.next(); String val = findValue (i); if (val != null && "".equals (val)) { val = null; } sb.append(" {").append(key).append(val == null ? "" : "," + val) .append('}'); if (k.hasNext()) { sb.append (','); } } sb.append (" }"); return sb.toString(); } public int findInt(String k, int Default) { try { return Integer.parseInt(findValue(k, String.valueOf(Default))); } catch (Throwable t) { return Default; } } /* public static void main(String[] a) throws Exception { System.out.print("enter line to parse> "); System.out.flush(); DataInputStream dis = new DataInputStream(System.in); String line = dis.readLine(); HeaderParser p = new HeaderParser(line); for (int i = 0; i < asize; ++i) { if (p.findKey(i) == null) break; String v = p.findValue(i); System.out.println(i + ") " +p.findKey(i) + "="+v); } System.out.println("Done!"); } */ }