下面是stackoverflow中關(guān)于數(shù)組方法的相關(guān)問題中,獲得最多票數(shù)的12個數(shù)組操作方法。
1. 聲明一個數(shù)組
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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" }; |
2. 輸出一個數(shù)組
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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] |
3. 從一個數(shù)組創(chuàng)建數(shù)組列表
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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] |
4. 檢查一個數(shù)組是否包含某個值
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String[] stringArray = { "a" , "b" , "c" , "d" , "e" }; boolean b = Arrays.asList(stringArray).contains( "a" ); System.out.println(b); // true |
5. 連接兩個數(shù)組
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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); |
6. 聲明一個內(nèi)聯(lián)數(shù)組(Array inline)
method(new String[]{"a", "b", "c", "d", "e"});
7. 把提供的數(shù)組元素放入一個字符串
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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 |
8. 將一個數(shù)組列表轉(zhuǎn)換為數(shù)組
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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); |
9. 將一個數(shù)組轉(zhuǎn)換為集(set)
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Set<String> set = new HashSet<String>(Arrays.asList(stringArray)); System.out.println(set); //[d, e, b, c, a] |
10. 逆向一個數(shù)組
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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] |
11. 移除數(shù)組中的元素
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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)); |
12. 將整數(shù)轉(zhuǎn)換為字節(jié)數(shù)組
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byte [] bytes = ByteBuffer.allocate( 4 ).putInt( 8 ).array(); for ( byte t : bytes) { System.out.format( "0x%x " , t); } |
以上就是對Java 數(shù)組資料的整理,后續(xù)繼續(xù)補(bǔ)充相關(guān)資料,謝謝大家對本站的支持!