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問題のCountAdapter.classは 解答は6/28の夜に一旦，集めました．

問題1

djava -c -o DJava CountAdapter.class の出力結果を参考にしながら，ちゃきちゃきやるしかないでしょう． あと， jasmin形式にしたアセンブラ も参考になります． というか，これらを参考にしないで解答を作るのは大変です！ (まぁ，時間があればできるけど) 
;; 384(d) bytes data (Revision: 4.9)

CA FE BA BE ; magic number
00 03 ; minor version
00 2D ; major version

00 19 ; constant pool number= 24(d) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

07 00 17 ;(00 01) Class => CountAdapter
01 00 0C 6D 6F 75 73 65 45 6E 74 65 72 65 64 ;(00 02) Utf8 = "mouseEntered"
01 00 06 3C 69 6E 69 74 3E ;(00 03) Utf8 = "<init>"
0C 00 03 00 07 ;(00 04) NameAndType => <init>:()V
0A 00 15 00 04 ;(00 05) Methodref => java/awt/event/MouseAdapter.<init>:()V
0C 00 14 00 10 ;(00 06) NameAndType => exit:(I)V
01 00 03 28 29 56 ;(00 07) Utf8 = "()V"
07 00 13 ;(00 08) Class => java/lang/System
01 00 04 43 6F 64 65 ;(00 09) Utf8 = "Code"
01 00 0C 6D 6F 75 73 65 50 72 65 73 73 65 64 ;(00 0A) Utf8 = "mousePressed"
0A 00 08 00 06 ;(00 0B) Methodref => java/lang/System.exit:(I)V
01 00 05 63 6F 75 6E 74 ;(00 0C) Utf8 = "count"
01 00 0F 43 6F 75 6E 74 41 64 61 70 74 65 72 2E 6A 32 ;(00 0D) Utf8 = "CountAdapter.j2"
01 00 0A 53 6F 75 72 63 65 46 69 6C 65 ;(00 0E) Utf8 = "SourceFile"
01 00 01 49 ;(00 0F) Utf8 = "I"
01 00 04 28 49 29 56 ;(00 10) Utf8 = "(I)V"
;
01 00 1E 28 4C 6A 61 76 61 2F 61 77 74 2F 65 76 65 6E 74 2F 4D 6F 75 73 65 45 76 65 6E 74 3B 29 56 ;(00 11) Utf8 = "(Ljava/awt/event/MouseEvent;)V"
01 00 1B 6A 61 76 61 2F 61 77 74 2F 65 76 65 6E 74 2F 4D 6F 75 73 65 41 64 61 70 74 65 72 ;(00 12) Utf8 = "java/awt/event/MouseAdapter"
01 00 10 6A 61 76 61 2F 6C 61 6E 67 2F 53 79 73 74 65 6D ;(00 13) Utf8 = "java/lang/System"
01 00 04 65 78 69 74 ;(00 14) Utf8 = "exit"
07 00 12 ;(00 15) Class => java/awt/event/MouseAdapter
09 00 01 00 18 ;(00 16) Fieldref => CountAdapter.count:I
01 00 0C 43 6F 75 6E 74 41 64 61 70 74 65 72 ;(00 17) Utf8 = "CountAdapter"
0C 00 0C 00 0F ;(00 18) NameAndType => count:I

;; class info. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

00 20 ; access flag= SUPER p.58
00 01 ; this class= "CountAdapter"
00 15 ; super class= "java/awt/event/MouseAdapter"

00 00 ; num. of implemented interface(s)= 0(d) ;;;;;;;;;;;;;;;;;;;;;;


00 01 ; num. of field(s)= 1(d) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;BEGIN field1(d) def.
00 02 ; access flag of method = PRIVATE p.62
00 0C ; method name ="count"
00 0F ; method type ="I"
;
00 00 ; num. of attribute(s), 0(d)
;
;END field1(d) def.

00 03 ; num. of methods(s)= 3(d) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;BEGIN method1(d) def.
00 00 ; access flag of method = p.73
00 03 ; method name ="<init>"
00 07 ; method type ="()V"
;
00 01 ; num. of attribute(s), 1(d)
;;begin attribute 1(d)
00 09 ; attribute type= "Code"
00 00 00 16 ; attribute length= 22(d)
;;
00 02 ; stacks limits
00 01 ; locals limits
00 00 00 0A ; length of codes = 10(d)
;;; codes
2A       ; aload_0
B7 00 05 ; invokespecial java/awt/event/MouseAdapter/<init>()V
2A       ; aload_0
03       ; iconst_0
B5 00 16 ; putfield CountAdapter/count I
B1       ; return
;;
00 00 ; num. of exception handler(s) = 0(d)
;;
00 00 ; num. of attr. of this code attr. = 0(d)
;;end attribute 1(d)
;
;END method1(d) def.

;BEGIN method2(d) def.
00 01 ; access flag of method = PUBLIC
00 02 ; method name ="mouseEntered"
00 11 ; method type ="(Ljava/awt/event/MouseEvent;)V"
;
00 01 ; num. of attribute(s), 1(d)
;;begin attribute 1(d)
00 09 ; attribute type= "Code"
00 00 00 17 ; attribute length= 23(d)
;;
00 03 ; stacks limits
00 02 ; locals limits
00 00 00 0B ; length of codes = 11(d)
;;; codes
2A       ; aload_0
59       ; dup
B4 00 16 ; getfield CountAdapter/count I
04       ; iconst_1
60       ; iadd
B5 00 16 ; putfield CountAdapter/count I
B1       ; return
;;
00 00 ; num. of exception handler(s) = 0(d)
;;
00 00 ; num. of attr. of this code attr. = 0(d)
;;end attribute 1(d)
;
;END method2(d) def.

;BEGIN method3(d) def.
00 01 ; access flag of method = PUBLIC
00 0A ; method name ="mousePressed"
00 11 ; method type ="(Ljava/awt/event/MouseEvent;)V"
;
00 01 ; num. of attribute(s), 1(d)
;;begin attribute 1(d)
00 09 ; attribute type= "Code"
00 00 00 14 ; attribute length= 20(d)
;;
00 01 ; stacks limits
00 02 ; locals limits
00 00 00 08 ; length of codes = 8(d)
;;; codes
2A       ; aload_0
B4 00 16 ; getfield CountAdapter/count I
B8 00 0B ; invokestatic java/lang/System/exit(I)V
B1       ; return
;;
00 00 ; num. of exception handler(s) = 0(d)
;;
00 00 ; num. of attr. of this code attr. = 0(d)
;;end attribute 1(d)
;
;END method3(d) def.

00 00 ; num. of class attribute(s)= 0(d) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;; successfully parsed.

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問題2

上記赤字の， B4 00 16 ; getfield CountAdapter/count I の部分のプール内の情報を図に書けばよい．

多分，答えを考えるより，図を描くほうがしんどかったかも． 工学分野では図を描いて考えるのが重要ですので， 慣れておいてくださいね．

あー，画はデジカメでとった人もいましたが， まぁ，それでもOKです．(ってか，そんなこと思いつかなかった)

問題3

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