Common-lang 研究 -- StringUtils 2

官方网站
http://commons.apache.org/lang/
下载地址
http://commons.apache.org/lang/download_lang.cgi
版本
commons-lang3-3.0-beta

测试方法

public static String trim(String str)
public static String trimToNull(String str)
public static String trimToEmpty(String str)

测试代码

String emptyString = "";
String nullString = null;
String blankString1 = " ";
String blankString2 = "\t\r\f\n";
String normalString1 = "Hello World!";
String normalString2 = "   Hello World!";
String normalString3 = "Hello World!    ";
String normalString4 = "    Hello World!    ";

System.out.println("----------------------trim------------------------");
//去掉字符串两端的控制符(control characters, char <= 32) , 如果输入为 null 则返回null 
System.out.println("emptyString \t--> " + StringUtils.trim(emptyString));
System.out.println("nullString \t--> " + StringUtils.trim(nullString));
System.out.println("blankString1 \t--> " + StringUtils.trim(blankString1));
System.out.println("blankString2 \t--> " + StringUtils.trim(blankString2));
System.out.println("normalString1 \t--> " + StringUtils.trim(normalString1));
System.out.println("normalString2 \t--> " + StringUtils.trim(normalString2));
System.out.println("normalString3 \t--> " + StringUtils.trim(normalString3));
System.out.println("normalString4 \t--> " + StringUtils.trim(normalString4));

System.out.println("----------------------trimToNull-------------------");
//去掉字符串两端的控制符(control characters, char <= 32) ,如果变为 null 或""，则返回 null 

System.out.println("emptyString \t--> " + StringUtils.trimToNull(emptyString));
System.out.println("nullString \t--> " + StringUtils.trimToNull(nullString));
System.out.println("blankString1 \t--> " + StringUtils.trimToNull(blankString1));
System.out.println("blankString2 \t--> " + StringUtils.trimToNull(blankString2));
System.out.println("normalString1 \t--> " + StringUtils.trimToNull(normalString1));
System.out.println("normalString2 \t--> " + StringUtils.trimToNull(normalString2));
System.out.println("normalString3 \t--> " + StringUtils.trimToNull(normalString3));
System.out.println("normalString4 \t--> " + StringUtils.trimToNull(normalString4));

System.out.println("----------------------trimToEmpty-------------------");
//去掉字符串两端的控制符(control characters, char <= 32) ,如果变为 null 或 "" ，则返回 "" 


System.out.println("emptyString \t--> " + StringUtils.trimToEmpty(emptyString));
System.out.println("nullString \t--> " + StringUtils.trimToEmpty(nullString));
System.out.println("blankString1 \t--> " + StringUtils.trimToEmpty(blankString1));
System.out.println("blankString2 \t--> " + StringUtils.trimToEmpty(blankString2));
System.out.println("normalString1 \t--> " + StringUtils.trimToEmpty(normalString1));
System.out.println("normalString2 \t--> " + StringUtils.trimToEmpty(normalString2));
System.out.println("normalString3 \t--> " + StringUtils.trimToEmpty(normalString3));
System.out.println("normalString4 \t--> " + StringUtils.trimToEmpty(normalString4));

测试结果

----------------------trim-------------------------
emptyString 	--> 
nullString 	--> null
blankString1 	--> 
blankString2 	--> 
normalString1 	--> Hello World!
normalString2 	--> Hello World!
normalString3 	--> Hello World!
normalString4 	--> Hello World!
----------------------trimToNull-----------------------
emptyString 	--> null
nullString 	--> null
blankString1 	--> null
blankString2 	--> null
normalString1 	--> Hello World!
normalString2 	--> Hello World!
normalString3 	--> Hello World!
normalString4 	--> Hello World!
----------------------trimToEmpty------------------------
emptyString 	--> 
nullString 	--> 
blankString1 	--> 
blankString2 	--> 
normalString1 	--> Hello World!
normalString2 	--> Hello World!
normalString3 	--> Hello World!
normalString4 	--> Hello World!