Arrays in compiling

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Simple array

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void daily(){
  int array[];
  int size=10;
  int value=123;
  array = new int[size];
  array[3] = value;
  value = array[5];
}

javap

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int[] daily();
    Code:
       0: bipush        10
       2: istore_2
       3: sipush        123
       6: istore_3
       7: iload_2
       8: newarray       int
      10: astore_1
      11: aload_1
      12: iconst_3
      13: iload_3
      14: iastore
      15: aload_1
      16: iconst_5
      17: iaload
      18: istore_3
      19: aload_1
      20: areturn

[7] load variable 10 to create a new array.
[10] save array’s reference to array variable.
Is aload_x show that the primary type array variable is an object ?

Object array

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Integer[] objectArray(){
  Integer oArray[];
  int count = 10;
  oArray = new Integer[count];
  oArray[0] = new Integer(7);
}

javap

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java.lang.Integer[] objectArray();
    Code:
       0: bipush        10
       2: istore_2
       3: iload_2
       // class java/lang/Integer
       4: anewarray     #2
       7: astore_1
       8: aload_1
       9: iconst_0
       // class java/lang/Integer
      10: new           #2
      13: dup
      14: bipush        7
      // Method java/lang/Integer."<init>":(I)V
      16: invokespecial #3
      20: aload_1
      21: areturn

Multianewarray

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int[][][] create3darray() {
  int matrix[][][];
  matrix = new int[2][3][4];
  return matrix;
}

javap

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int[][][] create3darray();
    Code:
       0: iconst_2
       1: iconst_3
       2: iconst_4
       // class "[[[I"
       3: multianewarray #4,  3
       7: astore_1
       8: aload_1
       9: areturn

Three constant used to create the 3 dimensional array.
Store to variable matrix, push to the top of stack.