ConstrettoUtils.java

/*
 * Copyright 2008 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.constretto.internal;

import java.util.*;

/**
 * @author <a href="mailto:kaare.nilsen@gmail.com">Kaare Nilsen</a>
 */
public class ConstrettoUtils {

    public static String asCsv(String[] arr) {
        StringBuffer tagcsv = new StringBuffer();
        for (String tag : arr) {
            if (tagcsv.length() > 0) {
                tagcsv.append(",");
            }
            tagcsv.append(tag);
        }
        return tagcsv.toString();
    }

    public static List<String> fromCSV(String csv) {
        List<String> elements = new ArrayList<String>();
        for (String element : csv.split(","))
            elements.add(element);
        return elements;
    }

    public static boolean isEmpty(String string){
        return (string == null || string.trim().length() == 0);
    }

    public static String substringBetween(String str, String open, String close) {
        if (str == null || open == null || close == null) {
            return null;
        }
        int start = str.indexOf(open);
        if (start != -1) {
            int end = str.indexOf(close, start + open.length());
            if (end != -1) {
                return str.substring(start + open.length(), end);
            }
        }
        return null;
    }

    public static String substringAfter(String str, String separator) {
        if (isEmpty(str)) {
            return str;
        }
        if (separator == null) {
            return "";
        }
        int pos = str.indexOf(separator);
        if (pos == -1) {
            return "";
        }
        return str.substring(pos + separator.length());
    }

    public static Locale toLocale(String str) {
        if (str == null) {
            return null;
        }
        int len = str.length();
        if (len != 2 && len != 5 && len < 7) {
            throw new IllegalArgumentException("Invalid locale format: " + str);
        }
        char ch0 = str.charAt(0);
        char ch1 = str.charAt(1);
        if (ch0 < 'a' || ch0 > 'z' || ch1 < 'a' || ch1 > 'z') {
            throw new IllegalArgumentException("Invalid locale format: " + str);
        }
        if (len == 2) {
            return new Locale(str, "");
        } else {
            if (str.charAt(2) != '_') {
                throw new IllegalArgumentException("Invalid locale format: " + str);
            }
            char ch3 = str.charAt(3);
            if (ch3 == '_') {
                return new Locale(str.substring(0, 2), "", str.substring(4));
            }
            char ch4 = str.charAt(4);
            if (ch3 < 'A' || ch3 > 'Z' || ch4 < 'A' || ch4 > 'Z') {
                throw new IllegalArgumentException("Invalid locale format: " + str);
            }
            if (len == 5) {
                return new Locale(str.substring(0, 2), str.substring(3, 5));
            } else {
                if (str.charAt(5) != '_') {
                    throw new IllegalArgumentException("Invalid locale format: " + str);
                }
                return new Locale(str.substring(0, 2), str.substring(3, 5), str.substring(6));
            }
        }
    }

    /**
	 * Merge the given Properties instance into the given Map,
	 * copying all properties (key-value pairs) over.
	 * <p>Uses <code>Properties.propertyNames()</code> to even catch
	 * default properties linked into the original Properties instance.
	 * @param props the Properties instance to merge (may be <code>null</code>)
	 * @param map the target Map to merge the properties into
	 */
    @SuppressWarnings("unchecked")
	public static void mergePropertiesIntoMap(Properties props, Map map) {
		if (map == null) {
			throw new IllegalArgumentException("Map must not be null");
		}
		if (props != null) {
			for (Enumeration en = props.propertyNames(); en.hasMoreElements();) {
				String key = (String) en.nextElement();
				map.put(key, props.getProperty(key));
			}
		}
	}
}