com.astamuse.asta4d.web.copyleft.SpringStringUtils Maven / Gradle / Ivy
package com.astamuse.asta4d.web.copyleft;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.List;
import java.util.StringTokenizer;
public class SpringStringUtils {
public SpringStringUtils() {
// TODO Auto-generated constructor stub
}
/**
* Tokenize the given String into a String array via a StringTokenizer.
* Trims tokens and omits empty tokens.
*
* The given delimiters string is supposed to 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 delimitedListToStringArray
*
* @param str
* the String to tokenize
* @param delimiters
* the delimiter characters, assembled as String (each of those
* characters is individually considered as delimiter).
* @return an array of the tokens
* @see java.util.StringTokenizer
* @see java.lang.String#trim()
* @see #delimitedListToStringArray
*/
public static String[] tokenizeToStringArray(String str, String delimiters) {
return tokenizeToStringArray(str, delimiters, true, true);
}
/**
* Tokenize the given String into a String array via a StringTokenizer.
*
* The given delimiters string is supposed to 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 delimitedListToStringArray
*
* @param str
* the String to tokenize
* @param delimiters
* the delimiter characters, assembled as String (each of those
* characters is individually considered as delimiter)
* @param trimTokens
* trim the tokens via String's 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 (null if the input String was
* null)
* @see java.util.StringTokenizer
* @see java.lang.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 tokens = new ArrayList();
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 Collection into a String array. The Collection must
* contain String elements only.
*
* @param collection
* the Collection to copy
* @return the String array (null if the passed-in Collection
* was null)
*/
public static String[] toStringArray(Collection collection) {
if (collection == null) {
return null;
}
return collection.toArray(new String[collection.size()]);
}
/**
* Copy the given Enumeration into a String array. The Enumeration must
* contain String elements only.
*
* @param enumeration
* the Enumeration to copy
* @return the String array (null if the passed-in Enumeration
* was null)
*/
public static String[] toStringArray(Enumeration enumeration) {
if (enumeration == null) {
return null;
}
List list = Collections.list(enumeration);
return list.toArray(new String[list.size()]);
}
/**
* Check that the given CharSequence is neither null nor of
* length 0. Note: Will return true for a CharSequence that
* purely consists of whitespace.
*
*
*
* StringUtils.hasLength(null) = false
* StringUtils.hasLength("") = false
* StringUtils.hasLength(" ") = true
* StringUtils.hasLength("Hello") = true
*
*
* @param str
* the CharSequence to check (may be null)
* @return true if the CharSequence is not null and has length
* @see #hasText(String)
*/
public static boolean hasLength(CharSequence str) {
return (str != null && str.length() > 0);
}
/**
* Check that the given String is neither null nor of length 0.
* Note: Will return true for a String that purely consists of
* whitespace.
*
* @param str
* the String to check (may be null)
* @return true if the String is not null and has length
* @see #hasLength(CharSequence)
*/
public static boolean hasLength(String str) {
return hasLength((CharSequence) str);
}
/**
* Check whether the given CharSequence has actual text. More specifically,
* returns true if the string not null, its length
* is greater than 0, and it contains at least one non-whitespace character.
*
*
*
* StringUtils.hasText(null) = false
* StringUtils.hasText("") = false
* StringUtils.hasText(" ") = false
* StringUtils.hasText("12345") = true
* StringUtils.hasText(" 12345 ") = true
*
*
* @param str
* the CharSequence to check (may be null)
* @return true if the CharSequence is not null,
* its length is greater than 0, and it does not contain whitespace
* only
* @see java.lang.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 whether the given String has actual text. More specifically,
* returns true if the string not null, its length
* is greater than 0, and it contains at least one non-whitespace character.
*
* @param str
* the String to check (may be null)
* @return true if the String is not null, its
* length is greater than 0, and it does not contain whitespace only
* @see #hasText(CharSequence)
*/
public static boolean hasText(String str) {
return hasText((CharSequence) str);
}
/**
* Count the occurrences of the substring in string s.
*
* @param str
* string to search in. Return 0 if this is null.
* @param sub
* string to search for. Return 0 if this is null.
*/
public static int countOccurrencesOf(String str, String sub) {
if (str == null || sub == null || str.length() == 0 || sub.length() == 0) {
return 0;
}
int count = 0;
int pos = 0;
int idx;
while ((idx = str.indexOf(sub, pos)) != -1) {
++count;
pos = idx + sub.length();
}
return count;
}
}