10分で完全に理解するInvokeDynamic / 10min To Understand InvokeDynamic

社内勉強会のLT資料です。

Transcript

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11. +7.ϚγϯޠΛ೷͍ͯΈΔ *OWPLFTKBWB package invoke.others; public class Invokes implements IInvoke { public static void main(String[] args) { int i = 1; Invokes.staticMethod(i); Invokes invs = new Invokes(); invs.method(i); IInvoke iinvs = invs; iinvs.interfaceMethod(i); } public int method(int i) { return i; } public static int staticMethod(int i) { return i; } @Override public int interfaceMethod(int i) { return i; } } interface IInvoke { int interfaceMethod(int i); } ❯ javac Invokes.java ❯ javap -v -p -s -constants Invokes.class > Invokes.jvm Compiled from "Invokes.java" public class invoke.others.Invokes implements invoke.others.IInvoke { : public static void main(java.lang.String[]); Code: 0: iconst_1 1: istore_1 2: iload_1 3: invokestatic #2 // Method staticMethod:(I)I 6: pop 7: new #3 // class invoke/others/Invokes 10: dup 11: invokespecial #4 // Method "<init>":()V 14: astore_2 15: aload_2 16: iload_1 17: invokevirtual #5 // Method method:(I)I 20: pop 21: aload_2 22: astore_3 23: aload_3 24: iload_1 25: invokeinterface #6, 2 // InterfaceMethod invoke/others/ IInvoke.interfaceMethod:(I)I 30: pop 31: return *OWPLFTKWN
    NBJOϝιουͷΈൈਮ
12. *OWPLFTKBWB package invoke.others; public class Invokes implements IInvoke { public static void main(String[] args) { int i = 1; Invokes.staticMethod(i); Invokes invs = new Invokes(); invs.method(i); IInvoke iinvs = invs; iinvs.interfaceMethod(i); } public int method(int i) { return i; } public static int staticMethod(int i) { return i; } @Override public int interfaceMethod(int i) { return i; } } interface IInvoke { int interfaceMethod(int i); } ❯ javac Invokes.java ❯ javap -v -p -s -constants Invokes.class > Invokes.jvm Compiled from "Invokes.java" public class invoke.others.Invokes implements invoke.others.IInvoke { : public static void main(java.lang.String[]); Code: 0: iconst_1 1: istore_1 2: iload_1 3: invokestatic #2 // Method staticMethod:(I)I 6: pop 7: new #3 // class invoke/others/Invokes 10: dup 11: invokespecial #4 // Method "<init>":()V 14: astore_2 15: aload_2 16: iload_1 17: invokevirtual #5 // Method method:(I)I 20: pop 21: aload_2 22: astore_3 23: aload_3 24: iload_1 25: invokeinterface #6, 2 // InterfaceMethod invoke/others/ IInvoke.interfaceMethod:(I)I 30: pop 31: return *OWPLFTKWN
    NBJOϝιουͷΈൈਮ +7.ϚγϯޠΛ೷͍ͯΈΔ
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16. *OWPLFTKBWB package invoke.others; public class Invokes implements IInvoke { public static void main(String[] args) { int i = 1; Invokes.staticMethod(i); Invokes invs = new Invokes(); invs.method(i); IInvoke iinvs = invs; iinvs.interfaceMethod(i); } public int method(int i) { return i; } public static int staticMethod(int i) { return i; } @Override public int interfaceMethod(int i) { return i; } } interface IInvoke { int interfaceMethod(int i); } ❯ javac Invokes.java ❯ javap -v -p -s -constants Invokes.class > Invokes.jvm Compiled from "Invokes.java" public class invoke.others.Invokes implements invoke.others.IInvoke { Constant pool: #2 = Methodref #3.#22 // invoke/others/Invokes.staticMethod:(I)I #3 = Class #23 // invoke/others/Invokes #16 = Utf8 (I)I #17 = Utf8 staticMethod #22 = NameAndType #17:#16 // staticMethod:(I)I #23 = Utf8 invoke/others/Invokes : public static void main(java.lang.String[]); Code: 0: iconst_1 1: istore_1 2: iload_1 3: invokestatic #2 // Method staticMethod:(I)I : *OWPLFTKWN
    ൈਮ +7.ϚγϯޠΛ೷͍ͯΈΔ
17. *OWPLFTKBWB package invoke.others; public class Invokes implements IInvoke { public static void main(String[] args) { int i = 1; Invokes.staticMethod(i); Invokes invs = new Invokes(); invs.method(i); IInvoke iinvs = invs; iinvs.interfaceMethod(i); } public int method(int i) { return i; } public static int staticMethod(int i) { return i; } @Override public int interfaceMethod(int i) { return i; } } interface IInvoke { int interfaceMethod(int i); } ❯ javac Invokes.java ❯ javap -v -p -s -constants Invokes.class > Invokes.jvm Compiled from "Invokes.java" public class invoke.others.Invokes implements invoke.others.IInvoke { Constant pool: #2 = Methodref #3.#22 // invoke/others/Invokes.staticMethod:(I)I #3 = Class #23 // invoke/others/Invokes #16 = Utf8 (I)I #17 = Utf8 staticMethod #22 = NameAndType #17:#16 // staticMethod:(I)I #23 = Utf8 invoke/others/Invokes : public static void main(java.lang.String[]); Code: 0: iconst_1 1: istore_1 2: iload_1 3: invokestatic #2 // Method staticMethod:(I)I : *OWPLFTKWN
    ൈਮ +7.ϚγϯޠΛ೷͍ͯΈΔ $POTUBOU
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18. *OWPLFTKBWB package invoke.others; public class Invokes implements IInvoke { public static void main(String[] args) { int i = 1; Invokes.staticMethod(i); Invokes invs = new Invokes(); invs.method(i); IInvoke iinvs = invs; iinvs.interfaceMethod(i); } public int method(int i) { return i; } public static int staticMethod(int i) { return i; } @Override public int interfaceMethod(int i) { return i; } } interface IInvoke { int interfaceMethod(int i); } ❯ javac Invokes.java ❯ javap -v -p -s -constants Invokes.class > Invokes.jvm Compiled from "Invokes.java" public class invoke.others.Invokes implements invoke.others.IInvoke { Constant pool: #2 = Methodref #3.#22 // invoke/others/Invokes.staticMethod:(I)I #3 = Class #23 // invoke/others/Invokes #16 = Utf8 (I)I #17 = Utf8 staticMethod #22 = NameAndType #17:#16 // staticMethod:(I)I #23 = Utf8 invoke/others/Invokes : public static void main(java.lang.String[]); Code: 0: iconst_1 1: istore_1 2: iload_1 3: invokestatic #2 // Method staticMethod:(I)I : *OWPLFTKWN
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19. *OWPLFTKBWB package invoke.others; public class Invokes implements IInvoke { public static void main(String[] args) { int i = 1; Invokes.staticMethod(i); Invokes invs = new Invokes(); invs.method(i); IInvoke iinvs = invs; iinvs.interfaceMethod(i); } public int method(int i) { return i; } public static int staticMethod(int i) { return i; } @Override public int interfaceMethod(int i) { return i; } } interface IInvoke { int interfaceMethod(int i); } ❯ javac Invokes.java ❯ javap -v -p -s -constants Invokes.class > Invokes.jvm Compiled from "Invokes.java" public class invoke.others.Invokes implements invoke.others.IInvoke { Constant pool: #2 = Methodref #3.#22 // invoke/others/Invokes.staticMethod:(I)I #3 = Class #23 // invoke/others/Invokes #16 = Utf8 (I)I #17 = Utf8 staticMethod #22 = NameAndType #17:#16 // staticMethod:(I)I #23 = Utf8 invoke/others/Invokes : public static void main(java.lang.String[]); Code: 0: iconst_1 1: istore_1 2: iload_1 3: invokestatic #2 // Method staticMethod:(I)I : *OWPLFTKWN
    ൈਮ +7.ϚγϯޠΛ೷͍ͯΈΔ ͭ·ΓɺίϯύΠϧ࣌Ͱ͸ͳ͘ɺ࣮ߦ࣌ʹ
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20. public static void main(java.lang.String[]); Code: 0: iconst_1 1: istore_1 2: iload_1 3: invokestatic #2 // Method staticMethod:(I)I : *OWPLFTKWN
    ൈਮ όΠφϦΛ೷͍ͯΈΔ invokestatic Operation Invoke a class (static) method Format 
 invokestatic
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 Forms invokestatic = 184 (0xb8) ͪͳΈʹόΠφϦ͸͜Μͳ͔Μ͡ɺ
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24. package invoke.dynamic; public class InvokeDynamicSimple { public static void main(String[] args) { Runnable r = () -> System.out.println("Hello"); r.run(); } } ❯ javac InvokeDynamicSimple.java ❯ javap -v -s -constants InvokeDynamicSimple.class > InvokeDynamicSimple.jvm public class invoke.dynamic.InvokeDynamicSimple Constant Pool: #2 = InvokeDynamic #0:#23 // #0:run:()Ljava/lang/Runnable; #23 = NameAndType #35:#36 // run:()Ljava/lang/Runnable; : { public static void main(java.lang.String[]); descriptor: ([Ljava/lang/String;)V flags: (0x0009) ACC_PUBLIC, ACC_STATIC Code: stack=1, locals=2, args_size=1 0: invokedynamic #2, 0 // InvokeDynamic #0:run:()Ljava/lang/Runnable; 5: astore_1 6: aload_1 7: invokeinterface #3, 1 // InterfaceMethod java/lang/Runnable.run:()V 12: return } SourceFile: "InvokeDynamicSimple.java" InnerClasses: public static final #50= #49 of #53; // Lookup=class java/lang/invoke/ MethodHandles$Lookup of class java/lang/invoke/MethodHandles BootstrapMethods: 0: #20 REF_invokeStatic java/lang/invoke/LambdaMetafactory.metafactory:(Ljava/lang/invoke/ MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/ MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/ CallSite; Method arguments: #21 ()V #22 REF_invokeStatic invoke/dynamic/InvokeDynamicSimple.lambda$main$0:()V #21 ()V *OWPLF%ZOBNJD4JNQMFKBWB *OWPLF%ZOBNJD4JNQMFKWN -BNCEB
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25. package invoke.dynamic; public class InvokeDynamicSimple { public static void main(String[] args) { Runnable r = () -> System.out.println("Hello"); r.run(); } } ❯ javac InvokeDynamicSimple.java ❯ javap -v -s -constants InvokeDynamicSimple.class > InvokeDynamicSimple.jvm public class invoke.dynamic.InvokeDynamicSimple Constant Pool: #2 = InvokeDynamic #0:#23 // #0:run:()Ljava/lang/Runnable; #23 = NameAndType #35:#36 // run:()Ljava/lang/Runnable; : { public static void main(java.lang.String[]); descriptor: ([Ljava/lang/String;)V flags: (0x0009) ACC_PUBLIC, ACC_STATIC Code: stack=1, locals=2, args_size=1 0: invokedynamic #2, 0 // InvokeDynamic #0:run:()Ljava/lang/Runnable; 5: astore_1 6: aload_1 7: invokeinterface #3, 1 // InterfaceMethod java/lang/Runnable.run:()V 12: return } SourceFile: "InvokeDynamicSimple.java" InnerClasses: public static final #50= #49 of #53; // Lookup=class java/lang/invoke/ MethodHandles$Lookup of class java/lang/invoke/MethodHandles BootstrapMethods: 0: #20 REF_invokeStatic java/lang/invoke/LambdaMetafactory.metafactory:(Ljava/lang/invoke/ MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/ MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/ CallSite; Method arguments: #21 ()V #22 REF_invokeStatic invoke/dynamic/InvokeDynamicSimple.lambda$main$0:()V #21 ()V *OWPLF%ZOBNJD4JNQMFKBWB *OWPLF%ZOBNJD4JNQMFKWN ࠶ͼ+7.ϚγϯޠΛ೷͍ͯΈΔ ϋΠग़·ͨ͠ɺJOWPLFEZOBNJD
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26. package invoke.dynamic; public class InvokeDynamicSimple { public static void main(String[] args) { Runnable r = () -> System.out.println("Hello"); r.run(); } } ❯ javac InvokeDynamicSimple.java ❯ javap -v -s -constants InvokeDynamicSimple.class > InvokeDynamicSimple.jvm public class invoke.dynamic.InvokeDynamicSimple Constant Pool: #2 = InvokeDynamic #0:#23 // #0:run:()Ljava/lang/Runnable; #23 = NameAndType #35:#36 // run:()Ljava/lang/Runnable; : { public static void main(java.lang.String[]); descriptor: ([Ljava/lang/String;)V flags: (0x0009) ACC_PUBLIC, ACC_STATIC Code: stack=1, locals=2, args_size=1 0: invokedynamic #2, 0 // InvokeDynamic #0:run:()Ljava/lang/Runnable; 5: astore_1 6: aload_1 7: invokeinterface #3, 1 // InterfaceMethod java/lang/Runnable.run:()V 12: return } SourceFile: "InvokeDynamicSimple.java" InnerClasses: public static final #50= #49 of #53; // Lookup=class java/lang/invoke/ MethodHandles$Lookup of class java/lang/invoke/MethodHandles BootstrapMethods: 0: #20 REF_invokeStatic java/lang/invoke/LambdaMetafactory.metafactory:(Ljava/lang/invoke/ MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/ MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/ CallSite; Method arguments: #21 ()V #22 REF_invokeStatic invoke/dynamic/InvokeDynamicSimple.lambda$main$0:()V #21 ()V *OWPLF%ZOBNJD4JNQMFKBWB *OWPLF%ZOBNJD4JNQMFKWN ࠶ͼ+7.ϚγϯޠΛ೷͍ͯΈΔ ͔͠͠$1ʹ
    
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    4USVDUVSFT bootstrap_method_attr_index The value of the bootstrap_method_attr_index item must be a valid index into the bootstrap_methods array of the bootstrap method table of this class file (§4.7.23).
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    Կ BootstrapMethods: 0: #20 REF_invokeStatic java/lang/invoke/LambdaMetafactory.metafactory:( Ljava/lang/invoke/MethodHandles$Lookup; Ljava/lang/String; Ljava/lang/invoke/MethodType; Ljava/lang/invoke/MethodType; Ljava/lang/invoke/MethodHandle; Ljava/lang/invoke/MethodType; )Ljava/lang/invoke/CallSite; Method arguments: #21 ()V #22 REF_invokeStatic invoke/dynamic/InvokeDynamicSimple.lambda$main$0:()V #21 ()V ͜Μͳॻࣜʹͳ͍ͬͯͯɺଟগෳࡶ͕ͩ
    
28. #PPU4USBQ.FUIPE#4.
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    Կ BootstrapMethods: 0: #20 REF_invokeStatic java/lang/invoke/LambdaMetafactory.metafactory:( Ljava/lang/invoke/MethodHandles$Lookup; Ljava/lang/String; Ljava/lang/invoke/MethodType; Ljava/lang/invoke/MethodType; Ljava/lang/invoke/MethodHandle; Ljava/lang/invoke/MethodType; )Ljava/lang/invoke/CallSite; Method arguments: #21 ()V #22 REF_invokeStatic invoke/dynamic/InvokeDynamicSimple.lambda$main$0:()V #21 ()V ௥Ճͷ੩తҾ਺ σϑΥϧτҾ਺
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    w ΠϯλʔϑΣʔεܦ༝ͷϝιου *OWPLF%ZOBNJD
    ͸ϚδͰ
    %ZOBNJD w *OWPLFEZOBNJD
    w ॳճ࣮ߦ࣌ʹ #PPUTUSBQ.FUIPE
    Ͱࢦఆ͞ ΕͨϝιουΛ࣮ߦ͠ɺ࣮ߦର ৅Λͦͷ݁ՌͰܾΊΔ ࣮ߦର৅Λ
    +BWBͷݴޠ࢓༷ʹै͍
    +7.಺Ͱݕࡧ࣮ͯ͠ߦ ͭ·Γ͜͏͍͏͜ͱ
31. w JOWPLFTUBUJD
    w 4UBUJDϝιου
    w JOWPLFTQFDJBM
    w ίϯετϥΫλͳͲ
    w JOWPLFWJSUVBM
    w Πϯελϯεϝιου
    w JOWPLFJOUFSGBDF
    w ΠϯλʔϑΣʔεܦ༝ͷϝιου *OWPLF%ZOBNJD
    ͸ϚδͰ
    %ZOBNJD w *OWPLFEZOBNJD
    w ॳճ࣮ߦ࣌ʹ #PPUTUSBQ.FUIPE
    Ͱࢦఆ͞ ΕͨϝιουΛ࣮ߦ͠ɺ࣮ߦର ৅Λͦͷ݁ՌͰܾΊΔ ίϯύΠϥ͕#4.Λు͖͑͢͞Ε͹ԿͰ΋͋Γ
    ࣮ߦ࣌ʹ+7.ʹଘࡏ͠ͳ͍ϝιου͢Βղܾɾ࣮ߦͰ͖Δਆͷ೗͖ྗ
    ࣮ࡍʹ
    -BNCEB
    Ͱ͸ɺ࣮ߦΫϥε͕#4.ʹΑΓ࿉੒͞ΕΔ ͭ·Γ͜͏͍͏͜ͱ ࣮ߦର৅Λ
    +BWBͷݴޠ࢓༷ʹै͍
    +7.಺Ͱݕࡧ࣮ͯ͠ߦ
32. ׬શཧղ🙌
33. ೳॻ͖͸͍͍ɺ
    όΠφϦ͕ݟ͍ͨ ͦ͏Ͱ͢Ͷʁ
34. ࿦ΑΓόΠφϦ package invoke.dynamic; public class InvokeDynamicSimple { public static void main(String[] args) { Runnable r = () -> System.out.println("Hello"); r.run(); } } public class invoke.dynamic.InvokeDynamicSimple Constant Pool: #2 = InvokeDynamic #0:#23 // #0:run:()Ljava/lang/Runnable; #23 = NameAndType #35:#36 // run:()Ljava/lang/Runnable; : { public static void main(java.lang.String[]); descriptor: ([Ljava/lang/String;)V flags: (0x0009) ACC_PUBLIC, ACC_STATIC Code: stack=1, locals=2, args_size=1 0: invokedynamic #2, 0 // InvokeDynamic #0:run:()Ljava/lang/Runnable; *OWPLF%ZOBNJD4JNQMFKBWB invokedynamic Operation Invoke a dynamically-computed call site Format invokedynamic
 indexbyte1
 indexbyte2
 0
 0
 Forms invokedynamic = 186 (0xba) Description First, the unsigned indexbyte1 and indexbyte2 are used to construct an index into the run-time constant pool of the current class (§2.6), The values of the third and fourth operand bytes must always be zero. JOWPLFEZOBNJD YCB *OWPLF%ZOBNJD4JNQMFDMBTT *OWPLF%ZOBNJD4JNQMFKWN
35. ࿦ΑΓόΠφϦ package invoke.dynamic; public class InvokeDynamicSimple { public static void main(String[] args) { Runnable r = () -> System.out.println("Hello"); r.run(); } } public class invoke.dynamic.InvokeDynamicSimple Constant Pool: #2 = InvokeDynamic #0:#23 // #0:run:()Ljava/lang/Runnable; #23 = NameAndType #35:#36 // run:()Ljava/lang/Runnable; : { public static void main(java.lang.String[]); descriptor: ([Ljava/lang/String;)V flags: (0x0009) ACC_PUBLIC, ACC_STATIC Code: stack=1, locals=2, args_size=1 0: invokedynamic #2, 0 // InvokeDynamic #0:run:()Ljava/lang/Runnable; *OWPLF%ZOBNJD4JNQMFKBWB invokedynamic Operation Invoke a dynamically-computed call site Format invokedynamic
 indexbyte1
 indexbyte2
 0
 0
 Forms invokedynamic = 186 (0xba) Description First, the unsigned indexbyte1 and indexbyte2 are used to construct an index into the run-time constant pool of the current class (§2.6), The values of the third and fourth operand bytes must always be zero. JOWPLFEZOBNJD YCB *OWPLF%ZOBNJD4JNQMFDMBTT *OWPLF%ZOBNJD4JNQMFKWN ͨͬͨ#ZUFͰ͜Ε͕දݱ͞Ε͍ͯΔͳΜͯ
    ඒ͍͠
    ͦ͏͸ࢥΘΜ͔Ͷʁ
36. ଓ͖͕ؾʹͳΔํɿ
    ʮ*OWPLF%ZOBNJD׬શʹཧղͨ͠ʯ JOWPLFEZOBNJDʹؔ࿈͢ΔશόΠφϦɺ
    -BNCEBͷ࣮ߦΛৄࡉʹઆ໌͠·ͨ͠
37. ,FZ
    5BLFBXBZT
    4BZ
    "HBJO  JOWPLFEZOBNJD
    ͷ൓ର͸
    JOWPLFTUBUJD
    ͡Όͳ͍
    㾎
    JOWPLFTUBUJD΋͍·͕͢ɺJOWPLF
    ͕ਓ͍·ͨ͠Ͷ
     JOWPLFTUBUJD
    ͸
    %ZOBNJD
    ͳ
    *OWPLF
    㾎+7.͕࣮ߦ࣌ʹಈతʹϝιουΛղܾ͍ͯ͠·ͨ͠Ͷ
     JOWPLFEZOBNJD
    ͸ϚδͰ
    %ZOBNJD
    㾎#4.ͰԿͰ΋࿉੒Ͱ͖Δਆͷ೗͖ྗͰͨ͠Ͷʂ
38. ͓લ΋
    +7.ʹ
    ͳΒͳ͍͔ʁ ͔͋͘͟Μ
39. Thank You For Your Kind Attention!