com.fr.stable

类 StringUtils

java.lang.Object

com.fr.stable.StringUtils

public class StringUtils
extends java.lang.Object

Operations on String that are null safe.

• IsEmpty/IsBlank - checks if a String contains text
• Trim/Strip - removes leading and trailing whitespace
• Equals - compares two strings null-safe
• startsWith - check if a String starts with a prefix null-safe
• endsWith - check if a String ends with a suffix null-safe
• IndexOf/LastIndexOf/Contains - null-safe index-of checks
• IndexOfAny/LastIndexOfAny/IndexOfAnyBut/LastIndexOfAnyBut - index-of any of a set of Strings
• ContainsOnly/ContainsNone/ContainsAny - does String contains only/none/any of these characters
• Substring/Left/Right/Mid - null-safe substring extractions
• SubstringBefore/SubstringAfter/SubstringBetween - substring extraction relative to other strings
• Split/Join - splits a String into an array of substrings and vice versa
• Remove/Delete - removes part of a String
• Replace/Overlay - Searches a String and replaces one String with another
• Chomp/Chop - removes the last part of a String
• LeftPad/RightPad/Center/Repeat - pads a String
• UpperCase/LowerCase/SwapCase/Capitalize/Uncapitalize - changes the case of a String
• CountMatches - counts the number of occurrences of one String in another
• IsAlpha/IsNumeric/IsWhitespace/IsAsciiPrintable - checks the characters in a String
• DefaultString - protects against a null input String
• Reverse/ReverseDelimited - reverses a String
• Abbreviate - abbreviates a string using ellipsis
• Difference - compares Strings and reports on their differences
• LevensteinDistance - the number of changes needed to change one String into another

The StringUtils class defines certain words related to String handling.

• null - null
• empty - a zero-length string ("")
• space - the space character (' ', char 32)
• whitespace - the characters defined by Character.isWhitespace(char)
• trim - the characters <= 32 as in String.trim()

StringUtils handles null input Strings quietly. That is to say that a null input will return null. Where a boolean or int is being returned details vary by method.

A side effect of the null handling is that a NullPointerException should be considered a bug in StringUtils (except for deprecated methods).

Methods in this class give sample code to explain their operation. The symbol * is used to indicate any input including null.

从以下版本开始:

1.0

版本:

$Id: StringUtils.java 635447 2008-03-10 06:27:09Z bayard $

作者:

Apache Jakarta Turbine, Jon S. Stevens, Daniel L. Rall, Greg Coladonato, Ed Korthof, Rand McNeely, Stephen Colebourne, Fredrik Westermarck, Holger Krauth, Alexander Day Chaffee, Henning P. Schmiedehausen, Arun Mammen Thomas, Gary Gregory, Phil Steitz, Al Chou, Michael Davey, Reuben Sivan, Chris Hyzer, Scott Johnson

另请参阅:

String

字段概要

字段

限定符和类型	字段和说明
static java.lang.String	BLANK 空白字符串
static java.lang.String	EMPTY 空字符串

方法概要

方法

限定符和类型	方法和说明
static java.lang.String	alwaysNotNull(java.lang.String txt) 生成一个非null的字符串
static boolean	contains(java.lang.String text, java.lang.String ch) 判断字符串text是否包含字符串ch
static java.lang.String	cutStringEndWith(java.lang.String org, java.lang.String mark) 1??
static java.lang.String	cutStringStartWith(java.lang.String org, java.lang.String mark) 处理已A字符开头的字符，去除掉A
static boolean	equals(java.lang.String obj1, java.lang.String obj2) peter:比较相等.
static boolean	equalsIgnore(java.lang.String str1, java.lang.String str2, java.lang.String attach) richer:判断两个字符串是否出去前后的附加字符串外是相等的 eg：equalsIgnore("/File/", "File", "/") == true 不支持传null path
static boolean	equalsIgnoreCase(java.lang.String s1, java.lang.String s2) 不区分大小写比较字符串
static int	getLength(java.lang.String str) 获取字符串的长度，如果是null则返回0
static boolean	isArrayType(java.lang.String text) 是否是数组类型的字符串
static boolean	isBlank(java.lang.String str) 检查一个字符串是否为空白字符串 StringUtils.isBlank(null) = true StringUtils.isBlank("") = true StringUtils.isBlank(" ") = true StringUtils.isBlank("bob") = false StringUtils.isBlank(" bob ") = false
static boolean	isEmpty(java.lang.String str) 检查一个字符串是否是空字符串 StringUtils.isEmpty(null) = true StringUtils.isEmpty("") = true StringUtils.isEmpty(" ") = false StringUtils.isEmpty("bob") = false StringUtils.isEmpty(" bob ") = false
static boolean	isNotBlank(java.lang.String str) 检查一个字符串是否不是空白字符串 StringUtils.isNotBlank(null) = false StringUtils.isNotBlank("") = false StringUtils.isNotBlank(" ") = false StringUtils.isNotBlank("bob") = true StringUtils.isNotBlank(" bob ") = true
static boolean	isNotEmpty(java.lang.String str) 检查一个字符串是否不为空字符串 StringUtils.isNotEmpty(null) = false StringUtils.isNotEmpty("") = false StringUtils.isNotEmpty(" ") = true StringUtils.isNotEmpty("bob") = true StringUtils.isNotEmpty(" bob ") = true
static java.lang.String	join(java.lang.String seperator, java.lang.String[] strings) carl:拼接数组字符
static java.lang.String	parseVersion(java.lang.String xmlDesignerVersion)
static java.lang.String	perfectEnd(java.lang.String str, java.lang.String attach) 检查一个字符串是否以某个指定的字符串结束，如果是的话不做改变，如果不是的话将把指定的字符串添加到原 字符串的末尾位置
static java.lang.String	perfectStart(java.lang.String str, java.lang.String attach) 检查一个字符串是否以某个指定的字符串开始，如果是的话不做改变，如果不是的话将把指定的字符串添加到原 字符串的起始位置
static java.lang.String	perfectSurround(java.lang.String str, java.lang.String attach)
static java.lang.String	rightPad(java.lang.String str, int size) 右侧填充空格直到字符串达到指定长度
static java.lang.String[][]	stringToArray(java.lang.String v)
static java.lang.String	subStringByByteLength(java.lang.String originString, java.lang.String charsetName, int byteLength) 根据字节数截取字符串
static java.util.StringTokenizer	text2StringTokenizer(java.lang.String text) text 做兼容类.
static java.lang.String	trim(java.lang.String str) Removes control characters (char <= 32) from both ends of this String, handling null by returning null.
static java.lang.String	trimToNull(java.lang.String str) 去掉字符串首尾的空白，如果剩余的结果是空白字符串那么返回null

从类继承的方法 java.lang.Object

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

字段详细资料

EMPTY

public static final java.lang.String EMPTY

空字符串

另请参阅:

常量字段值

BLANK

public static final java.lang.String BLANK

空白字符串

另请参阅:

常量字段值

方法详细资料

alwaysNotNull

public static java.lang.String alwaysNotNull(java.lang.String txt)

生成一个非null的字符串

参数:

txt - 原对象

返回:

非null的字符窜

isEmpty

public static boolean isEmpty(java.lang.String str)

检查一个字符串是否是空字符串

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

参数:

str - 被检查的字符串，可能为null

返回:

如果字符串为空或者是null则返回true，否则返回false

isNotEmpty

public static boolean isNotEmpty(java.lang.String str)

检查一个字符串是否不为空字符串

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

参数:

str - 被检查的字符串，可能是null

返回:

如果字符串不为空且不是null则返回true，否则返回false

isBlank

public static boolean isBlank(java.lang.String str)

检查一个字符串是否为空白字符串

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

参数:

str - 被检查的字符串

返回:

如果字符串为空、空格符或者null那么返回true，否则返回false

cutStringStartWith

public static java.lang.String cutStringStartWith(java.lang.String org,
                                  java.lang.String mark)

处理已A字符开头的字符，去除掉A

参数:

org - 原字符

mark - 标记字符

返回:

处理后的字符

cutStringEndWith

public static java.lang.String cutStringEndWith(java.lang.String org,
                                java.lang.String mark)

1??某一个特定字符B结束的字符AB，得到去掉B的前面的字符A

参数:

org - 全部字符

mark - 标记B

返回:

处理后的字符

isNotBlank

public static boolean isNotBlank(java.lang.String str)

检查一个字符串是否不是空白字符串

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

参数:

str - 被检查的字符串

返回:

如果字符串不是空字符串、空格符以及null那么就返回true，否则返回false

trim

public static java.lang.String trim(java.lang.String str)

Removes control characters (char <= 32) from both ends of this String, handling null by returning null.

The String is trimmed using String.trim(). Trim removes start and end characters <= 32. To strip whitespace use #(String).

To trim your choice of characters, use the #(String, String) methods.

 StringUtils.trim(null)          = null
 StringUtils.trim("")            = ""
 StringUtils.trim("     ")       = ""
 StringUtils.trim("abc")         = "abc"
 StringUtils.trim("    abc    ") = "abc"
 

参数:

str - the String to be trimmed, may be null

返回:

the trimmed string, null if null String input

trimToNull

public static java.lang.String trimToNull(java.lang.String str)

去掉字符串首尾的空白，如果剩余的结果是空白字符串那么返回null

perfectStart

public static java.lang.String perfectStart(java.lang.String str,
                            java.lang.String attach)

检查一个字符串是否以某个指定的字符串开始，如果是的话不做改变，如果不是的话将把指定的字符串添加到原 字符串的起始位置

perfectEnd

public static java.lang.String perfectEnd(java.lang.String str,
                          java.lang.String attach)

检查一个字符串是否以某个指定的字符串结束，如果是的话不做改变，如果不是的话将把指定的字符串添加到原 字符串的末尾位置

perfectSurround

public static java.lang.String perfectSurround(java.lang.String str,
                               java.lang.String attach)

getLength

public static int getLength(java.lang.String str)

获取字符串的长度，如果是null则返回0

equalsIgnore

public static boolean equalsIgnore(java.lang.String str1,
                   java.lang.String str2,
                   java.lang.String attach)

richer:判断两个字符串是否出去前后的附加字符串外是相等的 eg：equalsIgnore("/File/", "File", "/") == true 不支持传null path

contains

public static boolean contains(java.lang.String text,
               java.lang.String ch)

判断字符串text是否包含字符串ch

参数:

text - 主字符串

ch - 寻找的字符串

返回:

是否包含

text2StringTokenizer

public static java.util.StringTokenizer text2StringTokenizer(java.lang.String text)

text 做兼容类.

参数:

text - 文本兼容

返回:

StringTokenizer

join

public static java.lang.String join(java.lang.String seperator,
                    java.lang.String[] strings)

carl:拼接数组字符

parseVersion

public static java.lang.String parseVersion(java.lang.String xmlDesignerVersion)

isArrayType

public static boolean isArrayType(java.lang.String text)

是否是数组类型的字符串

参数:

text - 目标字符串

返回:

是否是数组类型的字符串

stringToArray

public static java.lang.String[][] stringToArray(java.lang.String v)

subStringByByteLength

public static java.lang.String subStringByByteLength(java.lang.String originString,
                                     java.lang.String charsetName,
                                     int byteLength)
                                              throws java.io.UnsupportedEncodingException

根据字节数截取字符串

参数:

originString - 原始字符串

charsetName - 字符编码

byteLength - 字节长度

返回:

截取后的字符串

抛出:

java.io.UnsupportedEncodingException

equals

public static boolean equals(java.lang.String obj1,
             java.lang.String obj2)

peter:比较相等.

参数:

obj1 - may be null.

obj2 - may be null.

equalsIgnoreCase

public static boolean equalsIgnoreCase(java.lang.String s1,
                       java.lang.String s2)

不区分大小写比较字符串

rightPad

public static java.lang.String rightPad(java.lang.String str,
                        int size)

右侧填充空格直到字符串达到指定长度