StringUtils常用方法(八)
阿新 • • 發佈:2018-12-07
如果你的專案是maven工程,首先在pom.xml中新增commons-lang3包的依賴
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.4</version>
</dependency>
判斷兩個字串是否相等
import org.apache.commons.lang3.StringUtils; StringUtils.equals("abc", null) = false StringUtils.equals("abc", "abc") = true StringUtils.equals("abc", "ABC") = false //忽略大小寫比較 StringUtils.equalsIgnoreCase("abc", "ABC") = true
比較字串的差異
//比較兩個字串,並返回它們不同的部分。更準確地說,返回第二個字串的其餘部分,從它與第一個不同的地方開始 StringUtils.difference("", "abc") = "abc" StringUtils.difference("abc", "") = "" StringUtils.difference("abc", "abc") = "" StringUtils.difference("abc", "ab") = "" StringUtils.difference("ab", "abxyz") = "xyz" StringUtils.difference("abcde", "abxyz") = "xyz" StringUtils.difference("abcde", "xyz") = "xyz" //比較兩個charsequence,並返回其中的索引,-1表示相等 StringUtils.indexOfDifference("", "") = -1 StringUtils.indexOfDifference("", "abc") = 0 StringUtils.indexOfDifference("abc", "") = 0 StringUtils.indexOfDifference("abc", "abc") = -1 StringUtils.indexOfDifference("ab", "abxyz") = 2 StringUtils.indexOfDifference("abcde", "abxyz") = 2 StringUtils.indexOfDifference("abcde", "xyz") = 0 //比較陣列中的所有字元序列,並返回其中的索引 StringUtils.indexOfDifference(new String[] {"", ""}) = -1 StringUtils.indexOfDifference(new String[] {"", null}) = 0 StringUtils.indexOfDifference(new String[] {"abc", null, null}) = 0 StringUtils.indexOfDifference(new String[] {null, null, "abc"}) = 0 StringUtils.indexOfDifference(new String[] {"", "abc"}) = 0 StringUtils.indexOfDifference(new String[] {"abc", ""}) = 0 StringUtils.indexOfDifference(new String[] {"abc", "abc"}) = -1 StringUtils.indexOfDifference(new String[] {"abc", "a"}) = 1 StringUtils.indexOfDifference(new String[] {"abcde", "xyz"}) = 0 StringUtils.indexOfDifference(new String[] {"i am a machine", "i am a robot"}) = 7
返回預設字串
//預設字串返回
StringUtils.defaultString("") = ""
StringUtils.defaultString("bat") = "bat"
//如果第一個字元為null則返回第二個字串,比if,else或者三目表示式好用多了
StringUtils.defaultString(null, "NULL") = "NULL"
StringUtils.defaultString("", "NULL") = ""
StringUtils.defaultString("bat", "NULL") = "bat"