Java Foundation--arrays Tools Class Ten common methods

Ten common methods of arrays tool class

Original link: http://blog.csdn.net/renfufei/article/details/16829457

0. Declaring an array

    New String[5];       = {"A", "B", "C", "D", "E"};       New String[]{"A", "B", "C", "D", "E"};  

1. Print an array

    int [] Intarray = {1, 2, 3, 4, 5 };       = arrays.tostring (intarray);              // print directly, the hash value      of the referenced object is printed // [email protected  ]    System.out.println (intarray);             // [1, 2, 3, 4, 5]      System.out.println (intarraystring);  

2. Create ArrayList based on an array

    String[] Stringarray = {"A", "B", "C", "D", "E" };      ArrayListNew arraylist<string>(arrays.aslist (Stringarray));       // [A, B, C, D, E]      System.out.println (arrayList);  

3. Check if the array contains a value

    String[] Stringarray = {"A", "B", "C", "D", "E" };       Boolean b = arrays.aslist (Stringarray). Contains ("a");       // true      System.out.println (b);  

4. Merge connections two arrays

    int [] Intarray = {1, 2, 3, 4, 5 };       int [] IntArray2 = {6, 7, 8, 9, ten };       // Apache Commons Lang gallery      int [] Combinedintarray = Arrayutils.addall (Intarray, intArray2);  

5. Declaring an inline array

    Method (new string[]{"A", "B", "C", "D", "E"});  

6. Concatenate (join) array with the given string

    // containing the provided list of elements       // Apache Common lang      String j = stringutils.join (new string[] {"A", "B", "C"}, ",");       // A, B, C      System.out.println (j);  

7. Convert ArrayList to Arrays

    String[] Stringarray = {"A", "B", "C", "D", "E" };      ArrayListNew arraylist<string>(arrays.aslist (Stringarray));       New string[arraylist.size ()];      Arraylist.toarray (Stringarr);        for (String S:stringarr)          System.out.println (s);  

8. Converting an array to a set

    New Hashset<string>(Arrays.aslist (Stringarray));       // [D, E, B, C, a]      SYSTEM.OUT.PRINTLN (set);  

9. Array element inversion

    int [] Intarray = {1, 2, 3, 4, 5 };      Arrayutils.reverse (intarray);       // [5, 4, 3, 2, 1]      System.out.println (arrays.tostring (Intarray));  

10. Removing elements

    int [] Intarray = {1, 2, 3, 4, 5 };       int [] removed = Arrayutils.removeelement (Intarray, 3); // Create a new array      System.out.println (arrays.tostring (removed));  

more--Convert int value to byte array

    byte [] bytes = Bytebuffer.allocate (4). Putint (8). Array ();               for (byte  t:bytes) {         System.out.format ("0x%x", T);      }  

Related reading:

1. Example of sorting Arrays
2. Read bytes from FileInputStream in Java
3. Java:convert a file to a byte array, and then convert byte array to a file.
4. Top Ten questions about Java collections

Java Foundation--arrays Tools Class Ten common methods