StringUtils.java

// Copyright 2012 Citrix Systems, Inc. Licensed under the
// Apache License, Version 2.0 (the "License"); you may not use this
// file except in compliance with the License.  Citrix Systems, Inc.
// reserves all rights not expressly granted by 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.
// 
// Automatically generated by addcopyright.py at 04/03/2012
package com.cloud.utils;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

// StringUtils exists in Apache Commons Lang, but rather than import the entire JAR to our system, for now
// just implement the method needed
public class StringUtils {
	private static final char[] hexChar = {
        '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'
    };
	
    public static String join(Iterable<? extends Object> iterable, String delim) {
        StringBuilder sb = new StringBuilder();
        if (iterable != null) {
            Iterator<? extends Object> iter = iterable.iterator();
            if (iter.hasNext()) {
                Object next = iter.next();
                sb.append(next.toString());
            }
            while (iter.hasNext()) {
                Object next = iter.next();
                sb.append(delim + next.toString());
            }
        }
        return sb.toString();
    }
    
    
	/**
	 * @param tags
	 * @return List of tags
	 */
    
    public static List<String> csvTagsToList(String tags) {
    	List<String> tagsList = new ArrayList<String>();
    	
    	if (tags != null) {
            String[] tokens = tags.split(",");
            for (int i = 0; i < tokens.length; i++) {
                tagsList.add(tokens[i].trim());
            }
        }
    	
    	return tagsList;
    }
    
	
    /**
	 * Converts a List of tags to a comma separated list
	 * @param tags
	 * @return String containing a comma separated list of tags
	 */
    
    public static String listToCsvTags(List<String> tagsList) {
    	String tags = "";
    	if (tagsList.size() > 0) {
    		for (int i = 0; i < tagsList.size(); i++) {
    			tags += tagsList.get(i);
    			if (i != tagsList.size() - 1) {
    				tags += ",";
    			}
    		}
    	} 
    	
    	return tags;
    }        
    
    public static String getExceptionStackInfo(Throwable e) {
    	StringBuffer sb = new StringBuffer();
    	
    	sb.append(e.toString()).append("\n");
    	StackTraceElement[] elemnents = e.getStackTrace();
    	for(StackTraceElement element : elemnents) {
    		sb.append(element.getClassName()).append(".");
    		sb.append(element.getMethodName()).append("(");
    		sb.append(element.getFileName()).append(":");
    		sb.append(element.getLineNumber()).append(")");
    		sb.append("\n");
    	}
    	
    	return sb.toString();
    }
    
    public static String unicodeEscape(String s) {
    	StringBuilder sb = new StringBuilder();
    	for (int i = 0; i < s.length(); i++) {
    	    char c = s.charAt(i);
    	    if ((c >> 7) > 0) {
	    		sb.append("\\u");
	    		sb.append(hexChar[(c >> 12) & 0xF]); // append the hex character for the left-most 4-bits
	    		sb.append(hexChar[(c >> 8) & 0xF]);  // hex for the second group of 4-bits from the left
	    		sb.append(hexChar[(c >> 4) & 0xF]);  // hex for the third group
	    		sb.append(hexChar[c & 0xF]);         // hex for the last group, e.g., the right most 4-bits
    	    }
    	    else {
	    		sb.append(c);
    	    }
    	}
    	return sb.toString();
    }
    
    public static String getMaskedPasswordForDisplay(String password) {
    	if(password == null || password.isEmpty())
    		return "*";
    	
    	StringBuffer sb = new StringBuffer();
    	sb.append(password.charAt(0));
    	for(int i = 1; i < password.length(); i++)
    		sb.append("*");
    	
    	return sb.toString();
    }
}