org.apache.zookeeper.common

Class StringUtils

java.lang.Object

org.apache.zookeeper.common.StringUtils

public class StringUtils
extends Object

Method Summary

Modifier and Type	Method and Description
static boolean	isBlank(String s) Returns true if the string is null or it does not contain any non space characters.
static boolean	isEmpty(String str) Checks if a String is empty ("") or null.
static String	joinStrings(List<String> list, String delim) This method takes a List<String> and a delimiter and joins the strings into a single string, where the original strings are separated using the given delimiter.
static List<String>	split(String value, String separator) This method returns an immutable List<String>, but different from String's split() it trims the results in the input String, and removes any empty string from the resulting List.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

split

public static List<String> split(String value,
                                 String separator)

This method returns an immutable List<String>, but different from String's split() it trims the results in the input String, and removes any empty string from the resulting List.

joinStrings

public static String joinStrings(List<String> list,
                                 String delim)

This method takes a List<String> and a delimiter and joins the strings into a single string, where the original strings are separated using the given delimiter. This method is a null-safe version of String.join(CharSequence, Iterable)

Note that if an individual element is null, then "null" is added.

Parameters:

list - a List that will have its elements joined together

delim - a sequence of characters that is used to separate each of the elements in the resulting String

Returns:

a new String that is composed from the elements argument or null if list is null

Throws:

NullPointerException - if delim is null

isBlank

public static boolean isBlank(String s)

Returns true if the string is null or it does not contain any non space characters.

Parameters:

s - the string

Returns:

true if the string is null or it does not contain any non space characters.

isEmpty

public static boolean isEmpty(String str)

Checks if a String is empty ("") or null.

 StringUtils.isEmpty(null)      = true
 StringUtils.isEmpty("")        = true
 StringUtils.isEmpty(" ")       = false
 StringUtils.isEmpty("bob")     = false
 StringUtils.isEmpty("  bob  ") = false
 

Parameters:

str - the String to check, may be null

Returns:

true if the String is empty or null