public class StringUtil extends Object
| 限定符和类型 | 方法和说明 |
|---|---|
static int |
compare(String str1,
String str2)
按照顺序比较两个字符串
String.compareTo(String) |
static int |
compare(String str1,
String str2,
boolean nullIsLess)
按照顺序比较两个字符串
String.compareTo(String) |
static boolean |
containsIgnoreCase(CharSequence str,
CharSequence searchStr)
忽略大小写判断查找的是否在字符对象理
|
static boolean |
equals(CharSequence cs1,
CharSequence cs2)
判断2个字符对象是否相等
|
static int |
indexOf(CharSequence seq,
CharSequence searchSeq)
返回指定子字符串第一次出现的字符串中的索引
|
static boolean |
isBlank(CharSequence cs)
判断字符串是否为空、判断过程中过滤空格换行符
|
static boolean |
isEmpty(CharSequence cs)
判断字符串是否是空
|
static boolean |
isEmptyNull(CharSequence cs)
判断字符串是否是空、并且判断字符串若是"null"也为空
|
static boolean |
isNotBlank(CharSequence cs)
判断字符串是否不为空、判断过程中过滤空格换行符
|
static boolean |
isNotEmpty(CharSequence cs)
判断字符串是否不是空
|
static boolean |
isNotEmptyNull(CharSequence cs)
判断字符串是否不为空、并且判断字符串若是"null"也为空
|
static String |
join(Iterable<?> iterable,
CharSequence cs)
将迭代器根据规则拆分后拼接成一个字符串,并以cs参数隔开
|
static String |
join(Iterator<?> iterator,
CharSequence cs)
将迭代器根据规则拆分后拼接成一个字符串,并以cs参数隔开
|
static int |
length(CharSequence cs)
获取字符对象的长度
|
static String[] |
split(CharSequence seq,
CharSequence splitSeq)
将字符串分裂成字符串数组.
|
static String |
substringAfter(String str,
String separator)
截取字符串分离之后的字符串
|
static String |
substringBeforeLast(String str,
String separator)
根据字符串截取最后出现的字符串之前
|
static String |
toUpperCaseFirstOne(String s)
首字母转大写
|
static String |
trim(String str)
删除空格
|
public static boolean isEmpty(CharSequence cs)
cs - 判断的字符串public static boolean isEmptyNull(CharSequence cs)
cs - 判断的字符串public static boolean isNotEmptyNull(CharSequence cs)
cs - 判断的字符串public static boolean isNotEmpty(CharSequence cs)
cs - 判断的字符串public static boolean isBlank(CharSequence cs)
cs - 判断的字符串public static boolean isNotBlank(CharSequence cs)
cs - 判断的字符串public static String join(Iterable<?> iterable, CharSequence cs)
iterable - 迭代器cs - 拼接的参数特殊情况:
1:若迭代器为空则返回null
2:若迭代器存放的是数据为空则返回null字符串拼接方式
3:若cs为空、则不加入分隔符
public static String join(Iterator<?> iterator, CharSequence cs)
iterator - 迭代器cs - 拼接的参数特殊情况
1:若迭代器为空则返回null
2:若迭代器存放的是数据为空则返回null字符串拼接方式
3:若cs为空、则不加入分隔符
示例:
StringUtil.join(null, *) = null
StringUtil.join([], *) = ""
StringUtil.join([null], *) = "null"
StringUtil.join(["a", "b", "c"], "--") = "a--b--c"
StringUtil.join(["a", "b", "c"], null) = "abc"
StringUtil.join(["a", "b", "c"], "") = "abc"
StringUtil.join([null, "", "a"], ',') = "null,null,a"
public static String substringBeforeLast(String str, String separator)
str - 字符串separator - 截取的字符串
示例:
StringUtil.substringBeforeLast(null, *) = null
StringUtil.substringBeforeLast("", *) = ""
StringUtil.substringBeforeLast("abcba", "b") = "abc"
StringUtil.substringBeforeLast("abc", "c") = "ab"
StringUtil.substringBeforeLast("a", "a") = ""
StringUtil.substringBeforeLast("a", "z") = "a"
StringUtil.substringBeforeLast("a", null) = "a"
StringUtil.substringBeforeLast("a", "") = "a"
public static int compare(String str1, String str2)
按照顺序比较两个字符串String.compareTo(String)
str1 - 要比较的字符串str2 - 要比较的字符串int = 0, 如果 str1 等于 str2 (或两者都为 null)int < 0, 如果 str1 小于 str2int > 0, 如果 str1 大于str2
示例:
StringUtil.compare(null, null) = 0
StringUtil.compare(null , "a") < 0
StringUtil.compare("a", null) > 0
StringUtil.compare("abc", "abc") = 0
StringUtil.compare("a", "b") < 0
StringUtil.compare("b", "a") > 0
StringUtil.compare("a", "B") > 0
StringUtil.compare("ab", "abc") < 0
String.compareTo(String)public static int compare(String str1, String str2, boolean nullIsLess)
按照顺序比较两个字符串String.compareTo(String)
str1 - 要比较的字符串str2 - 要比较的字符串nullIsLess - 是否认为null值小于非null值int = 0, 如果 str1 等于 str2 (或两者都为 null)int < 0, 如果 str1 小于 str2int > 0, 如果 str1 大于str2
示例:
StringUtil.compare(null, null, *) = 0
StringUtil.compare(null , "a", true) < 0
StringUtil.compare(null , "a", false) > 0
StringUtil.compare("a", null, true) > 0
StringUtil.compare("a", null, false) < 0
StringUtil.compare("abc", "abc", *) = 0
StringUtil.compare("a", "b", *) < 0
StringUtil.compare("b", "a", *) > 0
StringUtil.compare("a", "B", *) > 0
StringUtil.compare("ab", "abc", *) < 0
String.compareTo(String)public static String trim(String str)
删除空格
str - 要删除空格的字符串、可以为空
示例:
StringUtil.trim(null) = null
StringUtil.trim("") = ""
StringUtil.trim(" ") = ""
StringUtil.trim("abc") = "abc"
StringUtil.trim(" abc ") = "abc"
public static int indexOf(CharSequence seq, CharSequence searchSeq)
返回指定子字符串第一次出现的字符串中的索引
seq - 查找的字符串searchSeq - 查询字符串的索引
示例:
StringUtil.indexOf(null,*) = -1
StringUtil.indexOf(*,null) = -1
StringUtil.indexOf("","") = 0
StringUtil.indexOf("abca","a") = 0
StringUtil.indexOf("abca","c") = 2
String.indexOf(String)public static String[] split(CharSequence seq, CharSequence splitSeq)
seq - 需要分裂的字符串splitSeq - 分裂的标识public static boolean equals(CharSequence cs1, CharSequence cs2)
cs1 - 第一个字符对象cs2 - 第二个字符对象public static String toUpperCaseFirstOne(String s)
s - 转换的字符串public static boolean containsIgnoreCase(CharSequence str, CharSequence searchStr)
str - 字符对象searchStr - 查找的字符对象public static int length(CharSequence cs)
cs - 字符对象Copyright © 2019. All rights reserved.