6839802: java.dyn needs to be on the CORE_PKGS list

Summary: fix makefile to expose the new APIs in the core list; edit some javadocs for correctness
Reviewed-by: mr

make/common/Release.gmk

@@ -52,6 +52,9 @@ EXCLUDE_PROPWARN_PKGS = com.sun.java.swing.plaf          \
                         com.sun.java.swing.plaf.motif    \
                         com.sun.java.swing.plaf.gtk
 
+# This is a stopgap until 6839872 is fixed.
+EXCLUDE_PROPWARN_PKGS += sun.dyn
+
 # 64-bit solaris has a few special cases. We define the variable
 # SOLARIS64 for use in this Makefile to easily test those cases
 ifeq ($(PLATFORM), solaris)

make/docs/CORE_PKGS.gmk

@@ -97,6 +97,7 @@ CORE_PKGS =                                      \
   java.awt.print                                 \
   java.beans                                     \
   java.beans.beancontext                         \
+  java.dyn                                       \
   java.io                                        \
   java.lang                                      \
   java.lang.annotation                           \

src/share/classes/java/dyn/CallSite.java

@@ -28,18 +28,28 @@ package java.dyn;
 import sun.dyn.util.BytecodeName;
 
 /**
- * An <code>invokedynamic</code> call site, as reified to the bootstrap method.
- * Every instance of a call site corresponds to a distinct instance
- * of the <code>invokedynamic</code> instruction.
- * Call sites have state, one reference word, called the <code>target</code>,
- * and typed as a {@link MethodHandle}.  When this state is null (as it is
- * initially) the call site is in the unlinked state.  Otherwise, it is said
- * to be linked to its target.
+ * An {@code invokedynamic} call site, as reified by the
+ * containing class's bootstrap method.
+ * Every call site object corresponds to a distinct instance
+ * of the <code>invokedynamic</code> instruction, and vice versa.
+ * Every call site has one state variable, called the {@code target}.
+ * It is typed as a {@link MethodHandle}.  This state is never null, and
+ * it is the responsibility of the bootstrap method to produce call sites
+ * which have been pre-linked to an initial target method.
  * <p>
- * When an unlinked call site is executed, a bootstrap routine is called
- * to finish the execution of the call site, and optionally to link
- * the call site.
+ * (Note:  The bootstrap method may elect to produce call sites of a
+ * language-specific subclass of {@code CallSite}.  In such a case,
+ * the subclass may claim responsibility for initializing its target to
+ * a non-null value, by overriding {@link #initialTarget}.)
  * <p>
+ * An {@code invokedynamic} instruction which has not yet been executed
+ * is said to be <em>unlinked</em>.  When an unlinked call site is executed,
+ * the containing class's bootstrap method is called to manufacture a call site,
+ * for the instruction.  If the bootstrap method does not assign a non-null
+ * value to the new call site's target variable, the method {@link #initialTarget}
+ * is called to produce the new call site's first target method.
+ * <p>
+ * @see Linkage#registerBootstrapMethod(java.lang.Class, java.dyn.MethodHandle)
  * @author John Rose, JSR 292 EG
  */
 public class CallSite {
@@ -52,6 +62,15 @@ public class CallSite {
     final String name;
     final MethodType type;
 
+    /**
+     * Make a call site given the parameters from a call to the bootstrap method.
+     * The resulting call site is in an unlinked state, which means that before
+     * it is returned from a bootstrap method call it must be provided with
+     * a target method via a call to {@link CallSite#setTarget}.
+     * @param caller the class in which the relevant {@code invokedynamic} instruction occurs
+     * @param name the name specified by the {@code invokedynamic} instruction
+     * @param type the method handle type derived from descriptor of the {@code invokedynamic} instruction
+     */
     public CallSite(Object caller, String name, MethodType type) {
         this.caller = caller;
         this.name = name;
@@ -73,7 +92,9 @@ public class CallSite {
      * <p>
      * If the bootstrap method itself does not initialize the call site,
      * this method must be overridden, because it just raises an
-     * {@code InvokeDynamicBootstrapError}.
+     * {@code InvokeDynamicBootstrapError}, which in turn causes the
+     * linkage of the {@code invokedynamic} instruction to terminate
+     * abnormally.
      */
     protected MethodHandle initialTarget() {
         throw new InvokeDynamicBootstrapError("target must be initialized before call site is linked: "+this);
@@ -81,7 +102,7 @@ public class CallSite {
 
     /**
      * Report the current linkage state of the call site.  (This is mutable.)
-     * The value is null if and only if the call site is currently unlinked.
+     * The value maybe null only if the call site is currently unlinked.
      * When a linked call site is invoked, the target method is used directly.
      * When an unlinked call site is invoked, its bootstrap method receives
      * the call, as if via {@link Linkage#bootstrapInvokeDynamic}.
@@ -113,8 +134,9 @@ public class CallSite {
      * into the bootstrap method and/or the target methods used
      * at any given call site.
      * @param target the new target, or null if it is to be unlinked
-     * @throws WrongMethodTypeException if the new target is not null
-     *         and has a method type that differs from the call site's {@link #type}
+     * @throws NullPointerException if the proposed new target is null
+     * @throws WrongMethodTypeException if the proposed new target
+     *         has a method type that differs from the call site's {@link #type()}
      */
     public void setTarget(MethodHandle target) {
         checkTarget(target);
@@ -122,6 +144,7 @@ public class CallSite {
     }
 
     protected void checkTarget(MethodHandle target) {
+        target.type();  // provoke NPE
         if (!canSetTarget(target))
             throw new WrongMethodTypeException(String.valueOf(target));
     }
@@ -132,7 +155,7 @@ public class CallSite {
 
     /**
      * Report the class containing the call site.
-     * This is immutable static context.
+     * This is an immutable property of the call site, set from the first argument to the constructor.
      * @return class containing the call site
      */
     public Class<?> callerClass() {
@@ -141,7 +164,7 @@ public class CallSite {
 
     /**
      * Report the method name specified in the {@code invokedynamic} instruction.
-     * This is immutable static context.
+     * This is an immutable property of the call site, set from the second argument to the constructor.
      * <p>
      * Note that the name is a JVM bytecode name, and as such can be any
      * non-empty string, as long as it does not contain certain "dangerous"
@@ -187,7 +210,7 @@ public class CallSite {
      * which are derived from its bytecode-level invocation descriptor.
      * The types are packaged into a {@link MethodType}.
      * Any linked target of this call site must be exactly this method type.
-     * This is immutable static context.
+     * This is an immutable property of the call site, set from the third argument to the constructor.
      * @return method type specified by the call site
      */
     public MethodType type() {

src/share/classes/java/dyn/InvokeDynamic.java

@@ -26,10 +26,25 @@
 package java.dyn;
 
 /**
- * Syntactic marker interface to request javac to emit an {@code invokedynamic} instruction.
+ * Syntactic marker to request javac to emit an {@code invokedynamic} instruction.
+ * An {@code invokedynamic} instruction is a 5-byte bytecoded instruction
+ * which begins with an opcode byte of value 186 ({@code 0xBA}),
+ * and is followed by a two-byte index of a {@code NameAndType} constant
+ * pool entry, then by two zero bytes.  The constant pool reference gives
+ * the method name and argument and return types of the call site; there
+ * is no other information provided at the call site.
  * <p>
- * This type has no particular meaning as a class or interface supertype, and can never be instantiated.
+ * The {@code invokedynamic} instruction is incomplete without a target method.
+ * The target method is a property of the reified call site object
+ * (of type {@link CallSite}) which is in a one-to-one association with each
+ * corresponding {@code invokedynamic} instruction.  The call site object
+ * is initially produced by a <em>bootstrap method</em> associated with
+ * the call site, via the various overloadings of {@link Linkage#registerBootstrapMethod}.
+ * <p>
+ * The type {@code InvokeDynamic} has no particular meaning as a
+ * class or interface supertype, or an object type; it can never be instantiated.
  * Logically, it denotes a source of all dynamically typed methods.
+ * It may be viewed as a pure syntactic marker (an importable one) of static calls.
  * @author John Rose, JSR 292 EG
  */
 public final class InvokeDynamic {

src/share/classes/java/dyn/Linkage.java

@@ -37,16 +37,19 @@ public class Linkage {
     private Linkage() {}  // do not instantiate
 
     /**
-     * Register a bootstrap method for use for a given caller class.
-     * The method handle must be of a type equivalent to {@link Linkage#makeCallSite}.
+     * <em>PROVISIONAL API, WORK IN PROGRESS:</em>
+     * Register a <em>bootstrap method</em> to use when linking a given caller class.
+     * It must be a method handle of a type equivalent to {@link CallSite#CallSite}.
+     * In other words, it must act as a factory method which accepts the arguments
+     * to {@code CallSite}'s constructor (a class, a string, and a method type),
+     * and returns a {@code CallSite} object (possibly of a subclass of {@code CallSite}).
      * <p>
-     * The operation will fail with an exception if any of the following conditions hold:
+     * The registration will fail with an {@code IllegalStateException} if any of the following conditions hold:
      * <ul>
      * <li>The caller of this method is in a different package than the {@code callerClass},
      *     and there is a security manager, and its {@code checkPermission} call throws
      *     when passed {@link LinkagePermission}("registerBootstrapMethod",callerClass).
-     * <li>The given class already has a bootstrap method, either from an embedded
-     *     {@code BootstrapInvokeDynamic} classfile attribute, or from a previous
+     * <li>The given class already has a bootstrap method from a previous
      *     call to this method.
      * <li>The given class is already fully initialized.
      * <li>The given class is in the process of initialization, in another thread.
@@ -75,9 +78,10 @@ public class Linkage {
     }
 
     /**
+     * <em>PROVISIONAL API, WORK IN PROGRESS:</em>
      * Simplified version of registerBootstrapMethod for self-registration,
      * to be called from a static initializer.
-     * Finds a static method of type (CallSite, Object[]) -> Object in the
+     * Finds a static method of the required type in the
      * given class, and installs it on the caller.
      * @throws IllegalArgumentException if there is no such method
      */
@@ -92,9 +96,10 @@ public class Linkage {
     }
 
     /**
+     * <em>PROVISIONAL API, WORK IN PROGRESS:</em>
      * Simplified version of registerBootstrapMethod for self-registration,
      * to be called from a static initializer.
-     * Finds a static method of type (CallSite, Object[]) -> Object in the
+     * Finds a static method of the required type in the
      * caller's class, and installs it on the caller.
      * @throws IllegalArgumentException if there is no such method
      */
@@ -109,6 +114,7 @@ public class Linkage {
     }
 
     /**
+     * <em>PROVISIONAL API, WORK IN PROGRESS:</em>
      * Report the bootstrap method registered for a given class.
      * Returns null if the class has never yet registered a bootstrap method,
      * or if the class has explicitly registered a null bootstrap method.
@@ -125,8 +131,10 @@ public class Linkage {
         }
     }
 
-    /** The type of any bootstrap method is a three-argument method
-     * {@code (Class<?>, String, MethodType)} returning a {@code CallSite}.
+    /**
+     * <em>PROVISIONAL API, WORK IN PROGRESS:</em>
+     * The type of any bootstrap method is a three-argument method
+     * {@code (Class, String, MethodType)} returning a {@code CallSite}.
      */
     public static final MethodType BOOTSTRAP_METHOD_TYPE
             = MethodType.make(CallSite.class,
@@ -140,6 +148,7 @@ public class Linkage {
             new WeakHashMap<Class, MethodHandle>();
 
     /**
+     * <em>PROVISIONAL API, WORK IN PROGRESS:</em>
      * Invalidate all <code>invokedynamic</code> call sites everywhere.
      * <p>
      * When this method returns, every <code>invokedynamic</code> instruction
@@ -163,6 +172,7 @@ public class Linkage {
     }
 
     /**
+     * <em>PROVISIONAL API, WORK IN PROGRESS:</em>
      * Invalidate all <code>invokedynamic</code> call sites associated
      * with the given class.
      * (These are exactly those sites which report the given class

src/share/classes/java/dyn/MethodHandles.java

@@ -73,6 +73,7 @@ public class MethodHandles {
     }
 
     /**
+     * <em>PROVISIONAL API, WORK IN PROGRESS:</em>
      * A factory object for creating method handles, when the creation
      * requires access checking.  Method handles do not perform
      * access checks when they are called; this is a major difference
@@ -108,8 +109,10 @@ public class MethodHandles {
      * access.  In any of these cases, an exception will be
      * thrown from the attempted lookup.
      * In general, the conditions under which a method handle may be
-     * created for a method M are exactly as restrictive as the conditions
-     * under which the lookup class could have compiled a call to M.
+     * created for a method {@code M} are exactly as restrictive as the conditions
+     * under which the lookup class could have compiled a call to {@code M}.
+     * At least some of these error conditions are likely to be
+     * represented by checked exceptions in the final version of this API.
      */
     public static final
     class Lookup {
@@ -222,11 +225,11 @@ public class MethodHandles {
 
         /**
          * Produce an early-bound method handle for a virtual method,
-         * or a handle for a constructor, as if called from an {@code invokespecial}
+         * as if called from an {@code invokespecial}
          * instruction from {@code caller}.
-         * The type of the method handle will be that of the method or constructor,
+         * The type of the method handle will be that of the method,
          * with a suitably restricted receiver type (such as {@code caller}) prepended.
-         * The method or constructor and all its argument types must be accessible
+         * The method and all its argument types must be accessible
          * to the caller.
          * <p>
          * When called, the handle will treat the first argument as a receiver,

src/share/classes/java/dyn/MethodType.java

@@ -333,7 +333,7 @@ class MethodType {
 
     /** Convenience method for {@link #make(java.lang.Class, java.lang.Class[])}.
      * Convert all wrapper types to their corresponding primitive types.
-     * A return type of {@java.lang.Void} is changed to {@code void}.
+     * A return type of {@code java.lang.Void} is changed to {@code void}.
      * @return a version of the original type with all wrapper types replaced
      */
     public MethodType unwrap() {