The array tool class in Java

1, Boolean Equals (Array1,array2): Compares two arrays for equality.
Import Java.util.Arrays;
public class Ch03 {
public static void Main (string[] args) {
TODO auto-generated Method Stub
String[] str1={"1", "2", "3"};
String[] str2={"1", "2", New String ("3")};
System.out.println (Arrays.equals (str1, str2));//The result is: true
}
}

2, void sort (array): The elements of an array of arrays are sorted in ascending order
//Order an array
int[] score ={79,65,93,64,88};
Arrays.sort (score);//Sort an array
//sort: The effect is to sort an array in small to large
//str is also a reference address
String str = arrays.tostring (score ); The
//print method can print the value of a string directly
System.out.println (str);
Arrays.tostring (Score): Transforms an array into a string
3, String toString (array): Converts an array of arrays into a string.
Import java.util.Arrays;
public class Ch05 {
public static void Main (string[] args) {
//TODO auto-generated method stub
//tostring: Put An array is converted to a string
//define an array
int[] a={1,2,3};
System.out.println (a);//Print out the Hashcode code
SYSTEM.OUT.PRINTLN (Arrays.tostring (a));//print out an array of
}
}
4, void Fill (array,val): assigns the array all elements to Val.

//fill method: Replace all elements in the array with a value of
int[] num={1,2,3};
//Parameter 1: Array object
//Parameter 2: Replacement value
Arrays.fill (num, 6);
SYSTEM.OUT.PRINTLN (arrays.tostring (num));//Print Result: [6, 6, 6]
5, int binarysearch (array,val): Query element value val in array subscript
//binarysearch: Find the subscript of the corresponding element by means of dichotomy
//Use premise: must be sorted before you can use
char[] a={' A ', ' B ', ' C ', ' d ', ' e '};
int i = Arrays.binarysearch (A, ' d ');
System.out.println (i);//The result is: 3

char[] b={' e ', ' A ', ' C ', ' B ', ' d '};
Arrays.sort (b);
Int J=arrays.binarysearch (b, ' e ');
System.out.println (j);
6, copyof (array,length): Copies an array of arrays into a new array of length. That is, expand the array size.
//copyof: Copy the contents of an existing array into a new array
int[] a={1,2,3};
//Parameter 1: original array parameter 2: Length of new array
int[] b=arrays.copyof (A, a.length+ 1);
System.out.println (arrays.tostring (b));
//a and B have different address codes

==============================================
Int[] Arr=new int[] {11,33,44,66,55,22,99,88,77};
Arrays.sort (arr);
System.out.println (arr);
System.out.println (arrays.tostring (arr));
System.out.println (Arrays.binarysearch (arr, 55));
Output
[[Email protected]
[11, 22, 33, 44, 55, 66, 77, 88, 99]
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The array tool class in Java