本文分享了關(guān)于Java數(shù)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(huán)境或是在私人項目中,你都可以直接拿來用!

0. 聲明一個數(shù)組(Declare an array)
1 2 3 | 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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1. 在Java中輸出一個數(shù)組(Print an array in Java)
1 2 3 4 5 6 7 8 9 | int[] intArray = { 1, 2, 3, 4, 5 };
String intArrayString = Arrays.toString(intArray);
System.out.println(intArray);
System.out.println(intArrayString);
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2. 從數(shù)組中創(chuàng)建數(shù)組列表(Create an ArrayList from an array)
1 2 3 4 | String[] stringArray = { "a" , "b" , "c" , "d" , "e" };
ArrayList<String> arrayList = new ArrayList<String>(Arrays.asList(stringArray));
System.out.println(arrayList);
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3. 檢查數(shù)組中是否包含特定值(Check if an array contains a certain value)
1 2 3 4 | String[] stringArray = { "a" , "b" , "c" , "d" , "e" };
boolean b = Arrays.asList(stringArray).contains( "a" );
System.out.println(b);
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4. 連接兩個數(shù)組( Concatenate two arrays)
1 2 3 4 | int[] intArray = { 1, 2, 3, 4, 5 };
int[] intArray2 = { 6, 7, 8, 9, 10 };
int[] combinedIntArray = ArrayUtils.addAll(intArray, intArray2);
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5. 聲明一個數(shù)組內(nèi)鏈(Declare an array inline )
1 | method( new String[]{ "a" , "b" , "c" , "d" , "e" });
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6. 將數(shù)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)
1 2 3 4 5 | String j = StringUtils.join( new String[] { "a" , "b" , "c" }, ", " );
System.out.println(j);
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7. 將數(shù)組列表轉(zhuǎn)換成一個數(shù)組 (Covnert an ArrayList to an array)
1 2 3 4 5 6 | 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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8. 將數(shù)組轉(zhuǎn)換成一個集合(Convert an array to a set)
1 2 3 | Set<String> set = new HashSet<String>(Arrays.asList(stringArray));
System.out.println(set);
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9. 反向數(shù)組(Reverse an array)
1 2 3 4 | int[] intArray = { 1, 2, 3, 4, 5 };
ArrayUtils.reverse(intArray);
System.out.println(Arrays.toString(intArray));
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10. 刪除數(shù)組元素(Remove element of an array)
1 2 3 | int[] intArray = { 1, 2, 3, 4, 5 };
int[] removed = ArrayUtils.removeElement(intArray, 3);
System.out.println(Arrays.toString(removed));
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One more – convert int to byte array
1 2 3 4 5 | byte[] bytes = ByteBuffer.allocate(4).putInt(8).array();
for (byte t : bytes) {
System.out.format( "0x%x " , t);
}
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