檢查字符串是否為空或null或僅僅包含空格
? String test = "";
? String test1=" ";
? String test2 = "\n\n\t";
? String test3 = null;
? System.out.println( "test blank? " + StringUtils.isBlank( test ) );
? System.out.println( "test1 blank? " + StringUtils.isBlank( test1 ) );
? System.out.println( "test2 blank? " + StringUtils.isBlank( test2 ) );
? System.out.println( "test3 blank? " + StringUtils.isBlank( test3 ) );
? 運行結果:
? test blank? true
? test1 blank? true
? test2 blank? true
? test3 blank? true
? 相對應的還有一個StringUtils.isNotBlank(String str)
? StringUtils.isEmpty(String str)則檢查字符串是否為空或null(不檢查是否僅僅包含空格)
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分解字符串? StringUtils.split(null, *, *)??????????? = null
? StringUtils.split("", *, *)????????????? = []
? StringUtils.split("ab de fg", null, 0)?? = ["ab", "cd", "ef"]
? StringUtils.split("ab?? de fg", null, 0) = ["ab", "cd", "ef"]
? StringUtils.split("ab:cd:ef", ":", 0)??? = ["ab", "cd", "ef"]
? StringUtils.split("ab:cd:ef", ":", 1)??? = ["ab:cd:ef"]
? StringUtils.split("ab:cd:ef", ":", 2)??? = ["ab", "cd:ef"]
? StringUtils.split(String str,String separatorChars,int max) str為null時返回null
? separatorChars為null時默認為按空格分解,max為0或負數(shù)時分解沒有限制,max為1時返回整個字符串,max為分解成的個數(shù)(大于實際則無效)
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去除字符串前后指定的字符? StringUtils.strip(null, *)????????? = null
? StringUtils.strip("", *)??????????? = ""
? StringUtils.strip("abc", null)????? = "abc"
? StringUtils.strip(" abc ", null)??? = "abc"
? StringUtils.strip("? abcyx", "xyz") = "? abc"
? StringUtils.strip(String str,String stripChars) str為null時返回null,stripChars為null時默認為空格
? 創(chuàng)建醒目的Header(調(diào)試時用)
? public String createHeader( String title ) {
??? int width = 30;
??? String stars = StringUtils.repeat( "*", width);
??? String centered = StringUtils.center( title, width, "*" );
??? String heading = StringUtils.join(new Object[]{stars, centered, stars}, "\n");
??? return heading;
? }
? 調(diào)用createHeader("TEST")的輸出結果:
? ******************************
? ************ TEST ************
? ******************************
? 字符的全部反轉(zhuǎn)及以單個詞為單位的反轉(zhuǎn)
? String original = "In time, I grew tired of his babbling nonsense.";
? StringUtils.reverse( original )?? = ".esnesnon gnilbbab sih fo derit werg I ,emit nI"
? 以單個詞為單位的反轉(zhuǎn)
? public Sentence reverseSentence(String sentence) {
??? String reversed = StringUtils.chomp( sentence, "." );
??? reversed = StringUtils.reverseDelimited( reversed, ' ' );
??? reversed = reversed + ".";
??? return reversed;
? }
? String sentence = "I am Susan."
? reverseSentence( sentence ) )?? = "Susan am I."
? 檢查字符串是否僅僅包含數(shù)字、字母或數(shù)字和字母的混合
? String test1 = "ORANGE";
? String test2 = "ICE9";
? String test3 = "ICE CREAM";
? String test4 = "820B Judson Avenue";
? String test5 = "1976";
? 結果:
? boolean t1val = StringUtils.isAlpha( test1 ); // returns true
? boolean t2val = StringUtils.isAlphanumeric( test2 ); // returns true
? boolean t3val = StringUtils.isAlphaSpace( test3 ); // returns true
? boolean t4val = StringUtils.isAlphanumericSpace( test4 ); // returns true
? boolean t5val = StringUtils.isNumeric( test5 ); // returns true