FSAFlags.java

package org.xbib.elasticsearch.common.fsa;

import java.util.Set;

/**
 * FSA automaton flags. Where applicable, flags follow Daciuk's <code>fsa</code> package.
 */
public enum FSAFlags {
    /**
     * Daciuk: flexible FSA encoding.
     */
    FLEXIBLE(1),

    /**
     * Daciuk: stop bit in use.
     */
    STOPBIT(1 << 1),

    /**
     * Daciuk: next bit in use.
     */
    NEXTBIT(1 << 2),

    /**
     * Daciuk: tails compression.
     */
    TAILS(1 << 3),

	/*
     * These flags are outside of byte range (never occur in Daciuk's FSA).
	 */

    /**
     * The FSA contains right-language count numbers on states.
     *
     * @see FSA#getRightLanguageCount(int)
     */
    NUMBERS(1 << 8),

    /**
     * The FSA supports legacy built-in separator and filler characters (Daciuk's FSA package
     * compatibility).
     */
    SEPARATORS(1 << 9);

    /**
     * Bit mask for the corresponding flag.
     */
    public final int bits;

    FSAFlags(int bits) {
        this.bits = bits;
    }

    /**
     * @param flag  flag
     * @param flags flags
     * @return <code>true</code> if the corresponding flag is set in the bit set.
     */
    public static boolean isSet(int flags, FSAFlags flag) {
        return (flags & flag.bits) != 0;
    }

    public static short asShort(Set<FSAFlags> flags) {
        short value = 0;
        for (FSAFlags f : flags) {
            value |= f.bits;
        }
        return value;
    }
}