14.

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iconst_<n>

push the integer constant 0, 1, 2, 3, 4 or 5

Jasmin Syntax

     iconst_0 or     iconst_1 or     iconst_2 or     iconst_3 or     iconst_4 or     iconst_5 

Stack

Before	After
...	<n>
	...

Description

iconst_<n> represents the series of opcodes iconst_0, iconst_1, iconst_2, iconst_3, iconst_4 and iconst_5. These are used to push the constant ints 0 through 5 onto the stack. For example, to push the int zero onto the stack, use:

 iconst_0 ; push 0 onto the stack. 

Note that you could also use:

 bipush 0 ; push 0 onto the stack 

or

 sipush 0 ; push 0 onto the stack 

or

 ldc 0 ; push 0 onto the stack 

although these instructions are typically less efficient than the equivalent iconst_<n> and also take up more bytes in the class file.

Example

 iconst_0  ; push 0 onto the stack iconst_1  ; push 1 onto the stack iconst_2  ; push 2 onto the stack iconst_3  ; push 3 onto the stack iconst_4  ; push 4 onto the stack iconst_5  ; push 5 onto the stack 

Bytecode

Type	Description
u1	iconst_0 opcode = 0x03 (3)
u1	iconst_1 opcode = 0x04 (4)
u1	iconst_2 opcode = 0x05 (5)
u1	iconst_3 opcode = 0x06 (6)
u1	iconst_4 opcode = 0x07 (7)
u1	iconst_5 opcode = 0x08 (8)

See Also

bipush, sipush, ldc, ldc_w, ldc2_w, aconst_null, iconst_m1, lconst_<l>, fconst_<f>, dconst_<d>

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Java Virtual Machine, by Jon Meyer and Troy Downing, O'Reilly Associates