Private Methode kann in Interface in Java9 definiert werden

Es wurde. Wenn in Java8 die Standardeinstellung hinzugefügt wurde, traten häufig Probleme wie die Vererbung von Diamanten auf. Daher war ich neugierig und werde dies überprüfen.

Ergebnis

--Implementierungsklassen können keine privaten Schnittstellenmethoden aufrufen, ebenso wie private Methoden der Oberklasse nicht aufgerufen werden können.

Die private Methode Interface erfordert eine Entität
Dies wird passieren →![Java: Die Methode selbst fehlt oder wird als abstrakt deklariert](https://qiita-image-store.s3.amazonaws.com/0/48666/784afbda-fd6f-3041-e167- bc4ea96984a2.png)
Aus den oben genannten Gründen kann es nicht in Kombination mit der Standardeinstellung verwendet werden, für die auch eine Entität erforderlich ist.
Dies ist →![Java: Die Kombination der privaten und Standardqualifizierer ist ungültig](https://qiita-image-store.s3.amazonaws.com/0/48666/508efe96-9bd7-5d24-6fb7-395c76d6019b. png)
Es ist nicht erforderlich, Mehrfachvererbung, Ausblenden und Überschreiben für Methoden in Betracht zu ziehen, auf die von oben nicht verwiesen werden kann.

Fazit

Es wird als eine Funktion zum Erstellen einer Hilfsmethode innerhalb derselben Schnittstelle angesehen. Zumindest ist es nicht etwas, die Implementierung privater Methoden zu erzwingen oder für Muster von Vorlagenmethoden zu verwenden. Wenn Sie darüber nachdenken, haben Sie es vor langer Zeit erwähnt. → Java Interface Memo (Java Interface Memo von Hishidama) #Private Methode der Schnittstelle

Beispielklassenstruktur

キャプチャ.PNG

Beispielcode

`SampleInterfaceA.java`


public interface SampleInterfaceA {
    /**Das Übliche.*/
    String get();
    /**Explizit üblich.*/
    public abstract String getDetail();
    /**Standardmethode.*/
    default String getDefault() {return "default IA";}
    /**Ein statischer Typ.*/
    static String getStatic() {return "static IA";}
//Das ist nicht gut
//    /**Ein privater Typ.*/
//    private String getPrivate();
    /**privater statischer Typ.*/
    private static String getPrivateStatic() {return "private static IA";}
//Das ist auch nutzlos
//    /**Ein privater Standard-Typ.*/
//    private default String getPrivateDefault() {return "private default";}
    /**Ein privater Typ.*/
    private String getPrivate() {return "private IA";}
    /**Berücksichtigen Sie wie üblich detaillierte Signaturen.*/
    String getException() throws IOException;
    /**Private und detaillierte Unterschriftenprüfung.*/
    private String getPrivateException() throws IOException {return "private Exception IA";}
}

`SampleInterfaceB.java`


public interface SampleInterfaceB {
    String get();
    public abstract String getDetail();
    default String getDefault() {return "default IB";}
    static String getStatic() {return "static IB";}
    private static String getPrivateStatic() {return "private static IB";}
    private String getPrivate() {return "private IB";}
//Das ist von Anfang an ein Bösewicht
//    String getException() throws NoClassDefFoundError;
    private String getPrivateException() throws NoClassDefFoundError {return "private Exception IA";}
}

`ImplementA.java`


public class ImplementA implements SampleInterfaceA {
    @Override
    public String get() {return "public XA";}
    @Override
    public String getDetail() {return "public detail XA";}
    @Override
    public String toString() {
        try {
            return "ImplementA["
                    + this.get() + "\n"
                    + this.getDetail() + "\n"
                    + this.getDefault() + "\n"
                    + this.getException() + "\n"
                    + SampleInterfaceA.getStatic() + "\n"
//Die private Schnittstelle kann nicht von der Implementierungsklasse aufgerufen werden
//                    + super.getPrivate() + "\n"
//                    + SampleInterfaceA.getPrivateStatic() + "\n"
                    + this.getPrivate() + "\n"
                    + super.toString()
                    + "]";
        } catch (Exception e) {
            return "Okinai";
        }
    }

    @Override
    public String getException() throws IOException {return "public Exception XA";}
//Natürlich kann die Überschreibungsanmerkung nicht hinzugefügt werden
//    @Override
    private String getPrivate() {return "private XA";}
}

`ExtendsAImplementB.java`


public class ExtendsAImplementB extends ImplementA implements SampleInterfaceB {
    // SampleInterfaceA#get()Ist SampleInterfaceB#get()Da es dieselbe Signatur wie hat, wird die Implementierung der übergeordneten Klasse angewendet
    @Override
    public String getDefault() {
        return "public default extends XAB";
    }
    // SampleInterfaceA#getPrivate()Und SampleInterfaceB#getPrivate()Widerspricht nicht
    // SampleInterfaceA#getException()Und SampleInterfaceB#getException()Widerspricht nicht
}

`TestInterface.java`


public class TestInterface {
    public static void main(String... args) {
        System.out.println(new ImplementA());
        System.out.println();
        System.out.println(new ExtendsAImplementB());
    }
}

Beispielausführungsergebnis

ImplementA[public XA
public detail XA
default IA
public Exception XA
static IA
private XA
co.jp.qualysite.qm.java9.exam.privateInterface.ImplementA@13b6d03]

ImplementA[public XA
public detail XA
public default extends XAB
public Exception XA
static IA
private XA
co.jp.qualysite.qm.java9.exam.privateInterface.ExtendsAImplementB@783e6358]

Process finished with exit code 0

Beispiel für ein Javap-Ergebnis

`SampleInterfaceA.dec.txt`


  Last modified 2017/10/04; size 853 bytes
  MD5 checksum 43c60e1b8af3c04d6cbf41b17a047927
  Compiled from "SampleInterfaceA.java"
public interface co.jp.qualysite.qm.java9.exam.privateInterface.SampleInterfaceA
  minor version: 0
  major version: 53
  flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: #6                          // co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA
  super_class: #7                         // java/lang/Object
  interfaces: 0, fields: 0, methods: 8, attributes: 1
Constant pool:
   #1 = String             #26            // default IA
   #2 = String             #27            // static IA
   #3 = String             #28            // private static IA
   #4 = String             #29            // private IA
   #5 = String             #30            // private Exception IA
   #6 = Class              #31            // co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA
   #7 = Class              #32            // java/lang/Object
   #8 = Utf8               get
   #9 = Utf8               ()Ljava/lang/String;
  #10 = Utf8               getDetail
  #11 = Utf8               getDefault
  #12 = Utf8               Code
  #13 = Utf8               LineNumberTable
  #14 = Utf8               LocalVariableTable
  #15 = Utf8               this
  #16 = Utf8               Lco/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA;
  #17 = Utf8               getStatic
  #18 = Utf8               getPrivateStatic
  #19 = Utf8               getPrivate
  #20 = Utf8               getException
  #21 = Utf8               Exceptions
  #22 = Class              #33            // java/io/IOException
  #23 = Utf8               getPrivateException
  #24 = Utf8               SourceFile
  #25 = Utf8               SampleInterfaceA.java
  #26 = Utf8               default IA
  #27 = Utf8               static IA
  #28 = Utf8               private static IA
  #29 = Utf8               private IA
  #30 = Utf8               private Exception IA
  #31 = Utf8               co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA
  #32 = Utf8               java/lang/Object
  #33 = Utf8               java/io/IOException
{
  public abstract java.lang.String get();
    descriptor: ()Ljava/lang/String;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract java.lang.String getDetail();
    descriptor: ()Ljava/lang/String;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public java.lang.String getDefault();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #1                  // String default IA
         2: areturn
      LineNumberTable:
        line 16: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA;

  public static java.lang.String getStatic();
    descriptor: ()Ljava/lang/String;
    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: ldc           #2                  // String static IA
         2: areturn
      LineNumberTable:
        line 20: 0

  private static java.lang.String getPrivateStatic();
    descriptor: ()Ljava/lang/String;
    flags: (0x000a) ACC_PRIVATE, ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: ldc           #3                  // String private static IA
         2: areturn
      LineNumberTable:
        line 27: 0

  private java.lang.String getPrivate();
    descriptor: ()Ljava/lang/String;
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #4                  // String private IA
         2: areturn
      LineNumberTable:
        line 36: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA;

  public abstract java.lang.String getException() throws java.io.IOException;
    descriptor: ()Ljava/lang/String;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Exceptions:
      throws java.io.IOException

  private java.lang.String getPrivateException() throws java.io.IOException;
    descriptor: ()Ljava/lang/String;
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #5                  // String private Exception IA
         2: areturn
      LineNumberTable:
        line 42: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA;
    Exceptions:
      throws java.io.IOException
}
SourceFile: "SampleInterfaceA.java"

`SampleInterfaceB.dec.txt`


  Last modified 2017/10/03; size 831 bytes
  MD5 checksum ed3be9304a1489a8f0f77bb9e5657fe8
  Compiled from "SampleInterfaceB.java"
public interface co.jp.qualysite.qm.java9.exam.privateInterface.SampleInterfaceB
  minor version: 0
  major version: 53
  flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: #6                          // co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB
  super_class: #7                         // java/lang/Object
  interfaces: 0, fields: 0, methods: 7, attributes: 1
Constant pool:
   #1 = String             #25            // default IB
   #2 = String             #26            // static IB
   #3 = String             #27            // private static IB
   #4 = String             #28            // private IB
   #5 = String             #29            // private Exception IA
   #6 = Class              #30            // co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB
   #7 = Class              #31            // java/lang/Object
   #8 = Utf8               get
   #9 = Utf8               ()Ljava/lang/String;
  #10 = Utf8               getDetail
  #11 = Utf8               getDefault
  #12 = Utf8               Code
  #13 = Utf8               LineNumberTable
  #14 = Utf8               LocalVariableTable
  #15 = Utf8               this
  #16 = Utf8               Lco/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB;
  #17 = Utf8               getStatic
  #18 = Utf8               getPrivateStatic
  #19 = Utf8               getPrivate
  #20 = Utf8               getPrivateException
  #21 = Utf8               Exceptions
  #22 = Class              #32            // java/lang/NoClassDefFoundError
  #23 = Utf8               SourceFile
  #24 = Utf8               SampleInterfaceB.java
  #25 = Utf8               default IB
  #26 = Utf8               static IB
  #27 = Utf8               private static IB
  #28 = Utf8               private IB
  #29 = Utf8               private Exception IA
  #30 = Utf8               co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB
  #31 = Utf8               java/lang/Object
  #32 = Utf8               java/lang/NoClassDefFoundError
{
  public abstract java.lang.String get();
    descriptor: ()Ljava/lang/String;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract java.lang.String getDetail();
    descriptor: ()Ljava/lang/String;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public java.lang.String getDefault();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #1                  // String default IB
         2: areturn
      LineNumberTable:
        line 7: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB;

  public static java.lang.String getStatic();
    descriptor: ()Ljava/lang/String;
    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: ldc           #2                  // String static IB
         2: areturn
      LineNumberTable:
        line 10: 0

  private static java.lang.String getPrivateStatic();
    descriptor: ()Ljava/lang/String;
    flags: (0x000a) ACC_PRIVATE, ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: ldc           #3                  // String private static IB
         2: areturn
      LineNumberTable:
        line 13: 0

  private java.lang.String getPrivate();
    descriptor: ()Ljava/lang/String;
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #4                  // String private IB
         2: areturn
      LineNumberTable:
        line 16: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB;

  private java.lang.String getPrivateException() throws java.lang.NoClassDefFoundError;
    descriptor: ()Ljava/lang/String;
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #5                  // String private Exception IA
         2: areturn
      LineNumberTable:
        line 21: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB;
    Exceptions:
      throws java.lang.NoClassDefFoundError
}
SourceFile: "SampleInterfaceB.java"

`ImplementA.dec.txt`


  Last modified 2017/10/04; size 1789 bytes
  MD5 checksum 35cd13cc4e177ce294b094056750d7a2
  Compiled from "ImplementA.java"
public class co.jp.qualysite.qm.java9.exam.privateInterface.ImplementA implements co.jp.qualysite.qm.java9.exam.privateInterface.SampleInterfaceA
  minor version: 0
  major version: 53
  flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: #16                         // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA
  super_class: #17                        // java/lang/Object
  interfaces: 1, fields: 0, methods: 6, attributes: 3
Constant pool:
   #1 = Methodref          #17.#39        // java/lang/Object."<init>":()V
   #2 = String             #40            // public XA
   #3 = String             #41            // public detail XA
   #4 = Methodref          #16.#42        // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA.get:()Ljava/lang/String;
   #5 = Methodref          #16.#43        // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA.getDetail:()Ljava/lang/String;
   #6 = Methodref          #16.#44        // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA.getDefault:()Ljava/lang/String;
   #7 = Methodref          #16.#45        // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA.getException:()Ljava/lang/String;
   #8 = InterfaceMethodref #18.#46        // co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA.getStatic:()Ljava/lang/String;
   #9 = Methodref          #16.#47        // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA.getPrivate:()Ljava/lang/String;
  #10 = Methodref          #17.#48        // java/lang/Object.toString:()Ljava/lang/String;
  #11 = InvokeDynamic      #0:#52         // #0:makeConcatWithConstants:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
  #12 = Class              #53            // java/lang/Exception
  #13 = String             #54            //Okinai
  #14 = String             #55            // public Exception XA
  #15 = String             #56            // private XA
  #16 = Class              #57            // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA
  #17 = Class              #58            // java/lang/Object
  #18 = Class              #59            // co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA
  #19 = Utf8               <init>
  #20 = Utf8               ()V
  #21 = Utf8               Code
  #22 = Utf8               LineNumberTable
  #23 = Utf8               LocalVariableTable
  #24 = Utf8               this
  #25 = Utf8               Lco/jp/qualysite/qm/java9/exam/privateInterface/ImplementA;
  #26 = Utf8               get
  #27 = Utf8               ()Ljava/lang/String;
  #28 = Utf8               getDetail
  #29 = Utf8               toString
  #30 = Utf8               e
  #31 = Utf8               Ljava/lang/Exception;
  #32 = Utf8               StackMapTable
  #33 = Utf8               getException
  #34 = Utf8               Exceptions
  #35 = Class              #60            // java/io/IOException
  #36 = Utf8               getPrivate
  #37 = Utf8               SourceFile
  #38 = Utf8               ImplementA.java
  #39 = NameAndType        #19:#20        // "<init>":()V
  #40 = Utf8               public XA
  #41 = Utf8               public detail XA
  #42 = NameAndType        #26:#27        // get:()Ljava/lang/String;
  #43 = NameAndType        #28:#27        // getDetail:()Ljava/lang/String;
  #44 = NameAndType        #61:#27        // getDefault:()Ljava/lang/String;
  #45 = NameAndType        #33:#27        // getException:()Ljava/lang/String;
  #46 = NameAndType        #62:#27        // getStatic:()Ljava/lang/String;
  #47 = NameAndType        #36:#27        // getPrivate:()Ljava/lang/String;
  #48 = NameAndType        #29:#27        // toString:()Ljava/lang/String;
  #49 = Utf8               BootstrapMethods
  #50 = MethodHandle       6:#63          // REF_invokeStatic java/lang/invoke/StringConcatFactory.makeConcatWithConstants:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/invoke/CallSite;
  #51 = String             #64            // ImplementA[\u0001\n\u0001\n\u0001\n\u0001\n\u0001\n\u0001\n\u0001]
  #52 = NameAndType        #65:#66        // makeConcatWithConstants:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
  #53 = Utf8               java/lang/Exception
  #54 =Utf8 Okinai
  #55 = Utf8               public Exception XA
  #56 = Utf8               private XA
  #57 = Utf8               co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA
  #58 = Utf8               java/lang/Object
  #59 = Utf8               co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA
  #60 = Utf8               java/io/IOException
  #61 = Utf8               getDefault
  #62 = Utf8               getStatic
  #63 = Methodref          #67.#68        // java/lang/invoke/StringConcatFactory.makeConcatWithConstants:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/invoke/CallSite;
  #64 = Utf8               ImplementA[\u0001\n\u0001\n\u0001\n\u0001\n\u0001\n\u0001\n\u0001]
  #65 = Utf8               makeConcatWithConstants
  #66 = Utf8               (Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
  #67 = Class              #69            // java/lang/invoke/StringConcatFactory
  #68 = NameAndType        #65:#73        // makeConcatWithConstants:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/invoke/CallSite;
  #69 = Utf8               java/lang/invoke/StringConcatFactory
  #70 = Class              #75            // java/lang/invoke/MethodHandles$Lookup
  #71 = Utf8               Lookup
  #72 = Utf8               InnerClasses
  #73 = Utf8               (Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/invoke/CallSite;
  #74 = Class              #76            // java/lang/invoke/MethodHandles
  #75 = Utf8               java/lang/invoke/MethodHandles$Lookup
  #76 = Utf8               java/lang/invoke/MethodHandles
{
  public co.jp.qualysite.qm.java9.exam.privateInterface.ImplementA();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: invokespecial #1                  // Method java/lang/Object."<init>":()V
         4: return
      LineNumberTable:
        line 5: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       5     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/ImplementA;

  public java.lang.String get();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #2                  // String public XA
         2: areturn
      LineNumberTable:
        line 8: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/ImplementA;

  public java.lang.String getDetail();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #3                  // String public detail XA
         2: areturn
      LineNumberTable:
        line 13: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/ImplementA;

  public java.lang.String toString();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=7, locals=2, args_size=1
         0: aload_0
         1: invokevirtual #4                  // Method get:()Ljava/lang/String;
         4: aload_0
         5: invokevirtual #5                  // Method getDetail:()Ljava/lang/String;
         8: aload_0
         9: invokevirtual #6                  // Method getDefault:()Ljava/lang/String;
        12: aload_0
        13: invokevirtual #7                  // Method getException:()Ljava/lang/String;
        16: invokestatic  #8                  // InterfaceMethod co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceA.getStatic:()Ljava/lang/String;
        19: aload_0
        20: invokespecial #9                  // Method getPrivate:()Ljava/lang/String;
        23: aload_0
        24: invokespecial #10                 // Method java/lang/Object.toString:()Ljava/lang/String;
        27: invokedynamic #11,  0             // InvokeDynamic #0:makeConcatWithConstants:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
        32: areturn
        33: astore_1
        34: ldc           #13                 //String Okinai
        36: areturn
      Exception table:
         from    to  target type
             0    32    33   Class java/lang/Exception
      LineNumberTable:
        line 19: 0
        line 20: 1
        line 21: 5
        line 22: 9
        line 23: 13
        line 24: 16
        line 28: 20
        line 29: 24
        line 19: 32
        line 31: 33
        line 32: 34
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
           34       3     1     e   Ljava/lang/Exception;
            0      37     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/ImplementA;
      StackMapTable: number_of_entries = 1
        frame_type = 97 /* same_locals_1_stack_item */
          stack = [ class java/lang/Exception ]

  public java.lang.String getException() throws java.io.IOException;
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #14                 // String public Exception XA
         2: areturn
      LineNumberTable:
        line 38: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/ImplementA;
    Exceptions:
      throws java.io.IOException

  private java.lang.String getPrivate();
    descriptor: ()Ljava/lang/String;
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #15                 // String private XA
         2: areturn
      LineNumberTable:
        line 44: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/ImplementA;
}
SourceFile: "ImplementA.java"
InnerClasses:
  public static final #71= #70 of #74;    // Lookup=class java/lang/invoke/MethodHandles$Lookup of class java/lang/invoke/MethodHandles
BootstrapMethods:
  0: #50 REF_invokeStatic java/lang/invoke/StringConcatFactory.makeConcatWithConstants:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/invoke/CallSite;
    Method arguments:
      #51 ImplementA[\u0001\n\u0001\n\u0001\n\u0001\n\u0001\n\u0001\n\u0001]

`ExtendsAImplementB.dec.txt`


  Last modified 2017/10/04; size 612 bytes
  MD5 checksum 1fa0fadf291413f1950fd318148fe45a
  Compiled from "ExtendsAImplementB.java"
public class co.jp.qualysite.qm.java9.exam.privateInterface.ExtendsAImplementB extends co.jp.qualysite.qm.java9.exam.privateInterface.ImplementA implements co.jp.qualysite.qm.java9.exam.privateInterface.SampleInterfaceB
  minor version: 0
  major version: 53
  flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: #3                          // co/jp/qualysite/qm/java9/exam/privateInterface/ExtendsAImplementB
  super_class: #4                         // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA
  interfaces: 1, fields: 0, methods: 2, attributes: 1
Constant pool:
   #1 = Methodref          #4.#17         // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA."<init>":()V
   #2 = String             #18            // public default extends XAB
   #3 = Class              #19            // co/jp/qualysite/qm/java9/exam/privateInterface/ExtendsAImplementB
   #4 = Class              #20            // co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA
   #5 = Class              #21            // co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB
   #6 = Utf8               <init>
   #7 = Utf8               ()V
   #8 = Utf8               Code
   #9 = Utf8               LineNumberTable
  #10 = Utf8               LocalVariableTable
  #11 = Utf8               this
  #12 = Utf8               Lco/jp/qualysite/qm/java9/exam/privateInterface/ExtendsAImplementB;
  #13 = Utf8               getDefault
  #14 = Utf8               ()Ljava/lang/String;
  #15 = Utf8               SourceFile
  #16 = Utf8               ExtendsAImplementB.java
  #17 = NameAndType        #6:#7          // "<init>":()V
  #18 = Utf8               public default extends XAB
  #19 = Utf8               co/jp/qualysite/qm/java9/exam/privateInterface/ExtendsAImplementB
  #20 = Utf8               co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA
  #21 = Utf8               co/jp/qualysite/qm/java9/exam/privateInterface/SampleInterfaceB
{
  public co.jp.qualysite.qm.java9.exam.privateInterface.ExtendsAImplementB();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: invokespecial #1                  // Method co/jp/qualysite/qm/java9/exam/privateInterface/ImplementA."<init>":()V
         4: return
      LineNumberTable:
        line 3: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       5     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/ExtendsAImplementB;

  public java.lang.String getDefault();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: ldc           #2                  // String public default extends XAB
         2: areturn
      LineNumberTable:
        line 7: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  this   Lco/jp/qualysite/qm/java9/exam/privateInterface/ExtendsAImplementB;
}
SourceFile: "ExtendsAImplementB.java"

Überprüfen Sie die private Methode der Java9-Schnittstelle

Private Methode kann in Interface in Java9 definiert werden

Ergebnis

Fazit

Beispielklassenstruktur

Beispielcode

SampleInterfaceA.java

SampleInterfaceB.java

ImplementA.java

ExtendsAImplementB.java

TestInterface.java