MatchMode.java

package com.norteksoft.product.web.struts2.query;

//$Id: MatchMode.java,v 1.1.2.3 2003/09/27 14:10:35 oneovthafew Exp $

import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;

/**
 * Represents an strategy for matching strings using "like".
 * 
 * @see Example#enableLike(MatchMode)
 * @author Gavin King
 */
@SuppressWarnings({ "serial", "unchecked" })
public abstract class MatchMode implements Serializable {
	private final int intCode;
	private final String name;
	private static final Map INSTANCES = new HashMap();

	protected MatchMode(int intCode, String name) {
		this.intCode = intCode;
		this.name = name;
	}

	public String toString() {
		return name;
	}

	/**
	 * Match the entire string to the pattern
	 */
	public static final MatchMode EXACT = new MatchMode(0, "EXACT") {
		String toMatchString(String pattern) {
			return pattern;
		}
	};

	/**
	 * Match the start of the string to the pattern
	 */
	public static final MatchMode START = new MatchMode(1, "START") {
		String toMatchString(String pattern) {
			return pattern + '%';
		}
	};

	/**
	 * Match the end of the string to the pattern
	 */
	public static final MatchMode END = new MatchMode(2, "END") {
		String toMatchString(String pattern) {
			return '%' + pattern;
		}
	};

	/**
	 * Match the pattern anywhere in the string
	 */
	public static final MatchMode ANYWHERE = new MatchMode(3, "ANYWHERE") {
		String toMatchString(String pattern) {
			return '%' + pattern + '%';
		}
	};

	static {
		INSTANCES.put(new Integer(EXACT.intCode), EXACT);
		INSTANCES.put(new Integer(END.intCode), END);
		INSTANCES.put(new Integer(START.intCode), START);
		INSTANCES.put(new Integer(ANYWHERE.intCode), ANYWHERE);
	}

	private Object readResolve() {
		return INSTANCES.get(new Integer(intCode));
	}

	/**
	 * convert the pattern, by appending/prepending "%"
	 */
	abstract String toMatchString(String pattern);

}