128.

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aload

retrieve object reference from local variable

Jasmin Syntax

     aload <varnum> or     wide     aload <varnum> 

In the first form, <varnum> is an unsigned integer in the range 0 to 0xFF. In the second (wide) form, <varnum> is an unsigned integer in the range 0 to 0xFFFF.

Stack

Before	After
...	objectref
	...

Description

Retrieves an object reference from a local variable and pushes it onto the operand stack. The aload instruction takes a single parameter, <varnum>, an unsigned integer which indicates which local variable to retrieve. The object reference in that local variable is retrieved and placed on the stack. <varnum> must be a valid local variable number in the current frame.

Example

 aload 1         ; push object reference in local variable 1 onto the stack 

Bytecode

To access to local variables in the range 0-255, use:

Type	Description
u1	aload opcode = 0x19 (25)
u1	<varnum>

There is also a wide format for this instruction, which supports access to all local variables from 0 to 65535:

Type	Description
u1	wide opcode = 0xC4 (196)
u1	aload opcode = 0x19 (25)
u2	<varnum>

See Also

fload, iload, lload, dload, wide

Notes

If you use astore to store a returnAddress in a local variable, you cannot then use aload to retrieve the value of that local variable. Instead, if a local variable holds a returnAddress, your only choices are to (1) use ret to return to that address, or (2) use one of the store instructions to store some other value in the local variable.

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