int[] a = new int[10];

int a[] = new int[10];

　　int[] a = {1,2,3,4};
　　int[] a = new int[]{1,2,3,4};

public class ArrayTest
{
   public static void main(String[] args)
   {
       int[] a = {1, 2, 3};
       int[] b = {1, 2, 3};
       System.out.println(a.equals(b));
   }  
}

ArrayEqualsTest.java 
import java.util.Arrays;
public class ArrayEqualsTest
{
  //Compare the contents of two int arrays
  public static boolean isEquals(int[] a, int[] b)
  {
    if( a == null || b == null )
    { 
      return false;
    }
    if(a.length != b.length)
    {
      return false;
    }
    for(int i = 0; i < a.length; ++i )
    {
      if(a[i] != b[i])
      {
        return false;
      }
    }
    return true;
  }
  public static void main(String[] args)
  {
    int[] a = {1, 2, 3};
    int[] b = {1, 2, 3};
    System.out.println(isEquals(a,b));
    System.out.println(Arrays.equals(a,b));
  }
}

ArrayTest2.java
public class ArrayTest2
{
  public static void main(String[] args)
  {
    Person[] p = new Person[3];
    //未生成对象时，引用类型均为空
    System.out.println(p[0]);
    //生成对象之后，引用指向对象
    p[0] = new Person(10);
    p[1] = new Person(20);
    p[2] = new Person(30);
    for(int i = 0; i < p.length; i++)
    {
      System.out.println(p[i].age);
    }
  }
}
class Person
{
  int age;
  public Person(int age)
  {
    this.age = age;
  }
}

Person[] p = new Person[]{new Person(10), new Person(20), new Person(30)};

public class ArrayTest3
{
   public static void main(String[] args)
   {
       int[][] i = new int[2][3];
       System.out.println("Is i an Object? "
              + (i instanceof Object));
       System.out.println("Is i[0] an int[]? "
              + (i[0] instanceof int[]));
   }
}

public class ArrayTest4
{
  public static void main(String[] args)
  {
    //二维变长数组
    int[][] a = new int[3][];
    a[0] = new int[2];
    a[1] = new int[3];
    a[2] = new int[1];
    //Error: 不能空缺第一维大小
    //int[][] b = new int[][3];
  }
}

public class ArrayTest5
{
  public static void main(String[] args)
  {
    int[][] c = new int[][]{{1, 2, 3},{4},{5, 6, 7, 8}};
    for(int i = 0; i < c.length; ++i)
    {
      for(int j = 0; j < c[i].length; ++j)
      {
        System.out.print(c[i][j]+" ");    
      }
      System.out.println();
    }
  }
}