/*
 * Copyright (C) 2005  Markus Kraetzig
 * Created on 16.09.2005
 */
package com.jstatcom.util;

import java.io.Serializable;

/**
 * A case insensitive nonempty string. It stores the original upper/lowercase
 * representation of a string but uses only the uppercase representation for
 * comparisons. This is useful to keep the original string representation for
 * rendering, for example for portfolio names, but make only case insensitive
 * lookups. Furthermore, all strings all trimmed.
 * 

 * This class is immutable.
 * 
 * @author Markus Kraetzig 
 */
public final class CIString implements Comparable, Serializable {

    private final String origString;

    private final String upperCaseString;

    private final int hashCode;

    /**
     * Creates a portfolio string from a regular string.
     * 
     * @param s
     *            regular string
     * @throws IllegalArgumentException
     *             if null argument or if s is
     *             empty after trimming
     */
    public CIString(String s) {

        if (s == null)
            throw new IllegalArgumentException("Argument was null.");
        s = s.trim();
        if (s.length() == 0)
            throw new IllegalArgumentException(
                    "Argument string was empty after trim.");

        this.origString = s;
        this.upperCaseString = s.toUpperCase();
        this.hashCode = upperCaseString.hashCode();
    }

    /**
     * Gets the original string.
     * 
     * @return upper/lowercase string
     */
    public String toString() {
        return origString;
    }

    /**
     * Gets the uppercase string.
     * 
     * @return uppercase string representation
     */
    public String toUpperCase() {
        return upperCaseString;
    }

    /**
     * Overwrite equals to compare only uppercase representation.
     * 
     * @return true if o is PFString with same
     *         uppercase representation, false otherwise
     */
    public boolean equals(Object o) {
        if (!(o instanceof CIString))
            return false;
        if (o == this)
            return true;
        return upperCaseString.equals(((CIString) o).upperCaseString);
    }

    /**
     * Overwritten because equals was overwritten.
     * 
     * @return hashcode of uppercase representation
     */
    public int hashCode() {
        return hashCode;
    }

    public int compareTo(CIString s) {
        return upperCaseString.compareTo(s.upperCaseString);
    }
}