本文分享了關於Java數組最頂級的11大方法,幫助你解決工作流程問題,無論是運用在團隊環境或是在私人項目中,你都可以直接拿來用!
0. 聲明一個數組(Declare an array)
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String[] aArray = new String[5]; String[] bArray = { "a" , "b" , "c" , "d" , "e" }; String[] cArray = new String[]{ "a" , "b" , "c" , "d" , "e" }; |
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int[] intArray = { 1, 2, 3, 4, 5 }; String intArrayString = Arrays.toString(intArray); // print directly will print reference value System.out.println(intArray); // [I@7150bd4d System.out.println(intArrayString); // [1, 2, 3, 4, 5] |
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String[] stringArray = { "a" , "b" , "c" , "d" , "e" }; ArrayList<String> arrayList = new ArrayList<String>(Arrays.asList(stringArray)); System.out.println(arrayList); // [a, b, c, d, e] |
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String[] stringArray = { "a" , "b" , "c" , "d" , "e" }; boolean b = Arrays.asList(stringArray).contains( "a" ); System.out.println(b); // true |
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int[] intArray = { 1, 2, 3, 4, 5 }; int[] intArray2 = { 6, 7, 8, 9, 10 }; // Apache Commons Lang library int[] combinedIntArray = ArrayUtils.addAll(intArray, intArray2); |
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method( new String[]{ "a" , "b" , "c" , "d" , "e" }); |
6. 將數組元素加入到一個獨立的字符串中(Joins the elements of the provided array into a single String)
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// containing the provided list of elements // Apache common lang String j = StringUtils.join( new String[]
{ "a" , "b" , "c" }, ",
" ); System.out.println(j); // a, b, c |
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String[] stringArray = { "a" , "b" , "c" , "d" , "e" }; ArrayList<String> arrayList = new ArrayList<String>(Arrays.asList(stringArray)); String[] stringArr = new String[arrayList.size()]; arrayList.toArray(stringArr); for (String s : stringArr) System.out.println(s); |
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Set<String> set = new HashSet<String>(Arrays.asList(stringArray)); System.out.println(set); //[d, e, b, c, a] |
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int[] intArray = { 1, 2, 3, 4, 5 }; ArrayUtils.reverse(intArray); System.out.println(Arrays.toString(intArray)); //[5, 4, 3, 2, 1] |
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int[] intArray = { 1, 2, 3, 4, 5 }; int[] removed = ArrayUtils.removeElement(intArray, 3); //create
a new array System.out.println(Arrays.toString(removed)); |
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byte[] bytes = ByteBuffer.allocate(4).putInt(8).array(); for (byte t : bytes) { System.out.format( "0x%x
" , t); } |