/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* See LICENSE.txt included in this distribution for the specific
* language governing permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at LICENSE.txt.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
package org.opensolaris.opengrok.util;
import java.util.regex.Pattern;
/**
* Various String utility methods.
*
* @author austvik
*/
public final class StringUtils {
private StringUtils() {
// Only static utility methods
}
/**
* Returns true if the string is empty or only includes whitespace characters.
*
* @param str the string to be checked
* @return true if string is empty or only contains whitespace charadcters
*/
public static boolean isOnlyWhitespace(String str) {
for (int i = 0; i < str.length(); i++) {
if (!Character.isWhitespace(str.charAt(i))) {
return false;
}
}
return true;
}
/**
* Check whether two strings are equal. In contrast to the string's equal
* method this one allows {@code null} arguments.
* @param s1 string to compare with s2
* @param s2 string to compare with s1
* @return {@code true} if either both arguments ar {@code null} or both are
* {@code non-null} and s1.equals(s2).
*/
public static boolean isSame(String s1, String s2) {
if (s1 == null && s2 == null) {
return true;
}
if (s1 == null || s2 == null) {
return false;
}
return s1.equals(s2);
}
static final Pattern javaClassPattern =
Pattern.compile("([a-z][A-Za-z]*\\.)+[A-Z][A-Za-z0-9]*");
/**
* Returns true if the string is possibly a full java class name
*
* @param s the string to be checked
* @return true if string could be a java class name
*/
public static boolean isPossiblyJavaClass(String s) {
// Only match a small subset of possible class names to prevent false
// positives:
// - class must be qualified with a package name
// - only letters in package name, starting with lower case
// - class name must be in CamelCase, starting with upper case
return javaClassPattern.matcher(s).matches();
}
}