1 DalvikVSJvm

Bob Pan edited this page 2014-11-03 17:13:30 +08:00

Table of Contents

• Class Level
• Field Level
• Method Level
• Code Level

Class Level

1. AccessFlags: Dalvik remove ACC_SUPER, in a non interface class ACC_SUPER should been added.
2. Signature: Dalvik use a Ldalvik/annotation/Signature; annotation to store signature.
3. MemberClasses: Dalvik use a Ldalvik/annotation/MemberClasses; annotation, and *$1,*$2...*$n not included.
4. Ldalvik/annotation/InnerClass; TODO
5. Ldalvik/annotation/EnclosingClass; TODO
6. Ldalvik/annotation/EnclosingMethod; TODO

Field Level

1. Signature: Dalvik use a Ldalvik/annotation/Signature; annotation to store signature.

Method Level

1. Signature: Dalvik use a Ldalvik/annotation/Signature; annotation to store signature.
2. Throws: Dalvik use a Ldalvik/annotation/Throws; annotation to declare method throws.

Code Level

1. Register: Dalvik code is register-based, and put 'this' and parameters to the tail of the register array. e.g. a virtual davlik method which has 2 locals and 2 parameters, the register array is [local1,local2,this,param1,param2], but same method in jvm local array is [this,param1,param2,local1,local2]
2. Instruction: Dalvik use a 3-address code jvm use stack-based bytecode, more xLoad instruction should added. e.g. to call a virtual method ResourceBundle.getString(String) dalvik use [invoke-virtual {v2, v3};], and jvm use [aload 2; aload 3; invokevirtual;]
3. Zero and Null: Dalvik treat them as same