TagSet.java

/*
 * Copyright 2013 Hannes Janetzek
 *
 * This file is part of the OpenScienceMap project (http://www.opensciencemap.org).
 *
 * This program is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * This program 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with
 * this program. If not, see <http://www.gnu.org/licenses/>.
 */
package org.oscim.core;

import java.util.Arrays;

/**
 * The Class TagSet holds a set of Tags.
 */
public class TagSet {

	/** The Tags. */
	public Tag[] tags;

	/** The number of current Tags in set. */
	public int numTags;

	/**
	 * Instantiates a new TagSet with initial size of 10.
	 */
	public TagSet() {
		tags = new Tag[10];
	}

	/**
	 * Instantiates a new tag set initialized with the given size.
	 * 
	 * @param size the initial size.
	 */
	public TagSet(int size) {
		tags = new Tag[size];
	}

	/**
	 * Reset the TagSet to contain 0 tags.
	 */
	public void clear() {
		numTags = 0;
	}

	/**
	 * Clear. Reset the TagSet to contain 0 tags and null out tags.
	 */
	public void clearAndNullTags() {
		Arrays.fill(tags, null);
		numTags = 0;
	}

	/**
	 * Return Tags contained in TagSet as new array.
	 * 
	 * @return the tag[]
	 */
	public Tag[] asArray() {
		Tag[] result = new Tag[numTags];
		System.arraycopy(tags, 0, result, 0, numTags);
		return result;
	}

	/**
	 * Find Tag by given key.
	 * 
	 * @param key the key as intern String.
	 * @return the tag if found, null otherwise.
	 */
	public Tag get(String key) {
		for (int i = 0; i < numTags; i++) {
			if (tags[i].key == key)
				return tags[i];
		}
		return null;
	}

	/**
	 * Checks if any tag has the key 'key'.
	 * 
	 * @param key the key as intern String.
	 * @return true, iff any tag has the given key
	 */
	public boolean containsKey(String key) {
		for (int i = 0; i < numTags; i++) {
			if (tags[i].key == key)
				return true;
		}
		return false;
	}

	/**
	 * Get the value for a given key.
	 * 
	 * @param key the key as intern String
	 * @return the value when found, null otherwise
	 */
	public String getValue(String key) {
		for (int i = 0; i < numTags; i++) {
			if (tags[i].key == key)
				return tags[i].value;
		}
		return null;
	}

	/**
	 * Adds the Tag tag to TagSet.
	 * 
	 * @param tag the Tag to be added
	 */
	public void add(Tag tag) {
		if (numTags >= tags.length) {
			Tag[] tmp = tags;
			tags = new Tag[numTags + 4];
			System.arraycopy(tmp, 0, tags, 0, numTags);
		}
		tags[numTags++] = tag;
	}

	/**
	 * Sets the tags from 'tagArray'.
	 * 
	 * @param tagArray the tag array
	 */
	public void set(Tag[] tagArray) {
		int newTags = tagArray.length;
		if (newTags > tags.length)
			tags = new Tag[tagArray.length];
		System.arraycopy(tagArray, 0, tags, 0, newTags);

		numTags = newTags;
	}

	/**
	 * Checks if 'tag' is contained in TagSet.
	 * 
	 * @param tag the tag
	 * @return true, iff tag is in TagSet
	 */
	public boolean contains(Tag tag) {
		for (int i = 0; i < numTags; i++) {
			Tag t = tags[i];
			if ((t == tag) || (t.key == tag.key && t.value == tag.value))
				return true;
		}
		return false;
	}

	/**
	 * Checks if a Tag with given key and value is contained in TagSet.
	 * 
	 * @param key the key as intern String
	 * @param value the value as intern String
	 * @return true, iff any tag has the given key and value
	 */
	public boolean contains(String key, String value) {
		for (int i = 0; i < numTags; i++) {
			if (tags[i].key == key)
				return value.equals(tags[i].value);
		}
		return false;
	}

	@Override
	public String toString() {
		StringBuilder sb = new StringBuilder();
		for (int i = 0; i < numTags; i++)
			sb.append(tags[i]);

		return sb.toString();
	}
}