/*
* Copyright 2002-2015 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 com.navercorp.pinpoint.bootstrap.util.spring;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.StringTokenizer;
// copy 2015.04.16 -> master branch : e403aefe860d12f7427655f4fd2a59966a5d6442
// https://github.com/spring-projects/spring-framework/commits/master
/**
* Miscellaneous {@link String} utility methods.
*
* <p>Mainly for internal use within the framework; consider
* <a href="http://commons.apache.org/proper/commons-lang/">Apache's Commons Lang</a>
* for a more comprehensive suite of {@code String} utilities.
*
* <p>This class delivers some simple functionality that should really be
* provided by the core Java {@link String} and {@link StringBuilder}
* classes. It also provides easy-to-use methods to convert between
* delimited strings, such as CSV strings, and collections and arrays.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @author Keith Donald
* @author Rob Harrop
* @author Rick Evans
* @author Arjen Poutsma
* @author Sam Brannen
* @since 16 April 2001
*/
class StringUtils {
/**
* Check whether the given {@code CharSequence} contains actual <em>text</em>.
* <p>More specifically, this method returns {@code true} if the
* {@code CharSequence} is not {@code null}, its length is greater than
* 0, and it contains at least one non-whitespace character.
* <p><pre class="code">
* StringUtils.hasText(null) = false
* StringUtils.hasText("") = false
* StringUtils.hasText(" ") = false
* StringUtils.hasText("12345") = true
* StringUtils.hasText(" 12345 ") = true
* </pre>
* @param str the {@code CharSequence} to check (may be {@code null})
* @return {@code true} if the {@code CharSequence} is not {@code null},
* its length is greater than 0, and it does not contain whitespace only
* @see Character#isWhitespace
*/
public static boolean hasText(CharSequence str) {
if (!hasLength(str)) {
return false;
}
int strLen = str.length();
for (int i = 0; i < strLen; i++) {
if (!Character.isWhitespace(str.charAt(i))) {
return true;
}
}
return false;
}
/**
* Check that the given {@code CharSequence} is neither {@code null} nor
* of length 0.
* <p>Note: this method returns {@code true} for a {@code CharSequence}
* that purely consists of whitespace.
* <p><pre class="code">
* StringUtils.hasLength(null) = false
* StringUtils.hasLength("") = false
* StringUtils.hasLength(" ") = true
* StringUtils.hasLength("Hello") = true
* </pre>
* @param str the {@code CharSequence} to check (may be {@code null})
* @return {@code true} if the {@code CharSequence} is not {@code null} and has length
* @see #hasText(String)
*/
public static boolean hasLength(CharSequence str) {
return (str != null && str.length() > 0);
}
/**
* Tokenize the given {@code String} into a {@code String} array via a
* {@link StringTokenizer}.
* <p>Trims tokens and omits empty tokens.
* <p>The given {@code delimiters} string can consist of any number of
* delimiter characters. Each of those characters can be used to separate
* tokens. A delimiter is always a single character; for multi-character
* delimiters, consider using {@link #delimitedListToStringArray}.
* @param str the {@code String} to tokenize
* @param delimiters the delimiter characters, assembled as a {@code String}
* (each of the characters is individually considered as a delimiter)
* @return an array of the tokens
* @see java.util.StringTokenizer
* @see String#trim()
* @see #delimitedListToStringArray
*/
public static String[] tokenizeToStringArray(String str, String delimiters) {
return tokenizeToStringArray(str, delimiters, true, true);
}
/**
* Tokenize the given {@code String} into a {@code String} array via a
* {@link StringTokenizer}.
* <p>The given {@code delimiters} string can consist of any number of
* delimiter characters. Each of those characters can be used to separate
* tokens. A delimiter is always a single character; for multi-character
* delimiters, consider using {@link #delimitedListToStringArray}.
* @param str the {@code String} to tokenize
* @param delimiters the delimiter characters, assembled as a {@code String}
* (each of the characters is individually considered as a delimiter)
* @param trimTokens trim the tokens via {@link String#trim()}
* @param ignoreEmptyTokens omit empty tokens from the result array
* (only applies to tokens that are empty AFTER trimming; StringTokenizer
* will not consider subsequent delimiters as token in the first place).
* @return an array of the tokens ({@code null} if the input {@code String}
* was {@code null})
* @see java.util.StringTokenizer
* @see String#trim()
* @see #delimitedListToStringArray
*/
public static String[] tokenizeToStringArray(
String str, String delimiters, boolean trimTokens, boolean ignoreEmptyTokens) {
if (str == null) {
return null;
}
StringTokenizer st = new StringTokenizer(str, delimiters);
List<String> tokens = new ArrayList<String>();
while (st.hasMoreTokens()) {
String token = st.nextToken();
if (trimTokens) {
token = token.trim();
}
if (!ignoreEmptyTokens || token.length() > 0) {
tokens.add(token);
}
}
return toStringArray(tokens);
}
/**
* Copy the given {@code Collection} into a {@code String} array.
* <p>The {@code Collection} must contain {@code String} elements only.
* @param collection the {@code Collection} to copy
* @return the {@code String} array ({@code null} if the supplied
* {@code Collection} was {@code null})
*/
public static String[] toStringArray(Collection<String> collection) {
if (collection == null) {
return null;
}
return collection.toArray(new String[collection.size()]);
}
}