1.1 --- a/src/jdk/internal/dynalink/DynamicLinkerFactory.java Thu Nov 06 17:06:56 2014 +0100
1.2 +++ b/src/jdk/internal/dynalink/DynamicLinkerFactory.java Mon Nov 03 09:49:52 2014 +0100
1.3 @@ -97,6 +97,7 @@
1.4 import jdk.internal.dynalink.linker.GuardingDynamicLinker;
1.5 import jdk.internal.dynalink.linker.GuardingTypeConverterFactory;
1.6 import jdk.internal.dynalink.linker.LinkRequest;
1.7 +import jdk.internal.dynalink.linker.MethodTypeConversionStrategy;
1.8 import jdk.internal.dynalink.support.AutoDiscovery;
1.9 import jdk.internal.dynalink.support.BottomGuardingDynamicLinker;
1.10 import jdk.internal.dynalink.support.ClassLoaderGetterContextProvider;
1.11 @@ -105,6 +106,7 @@
1.12 import jdk.internal.dynalink.support.DefaultPrelinkFilter;
1.13 import jdk.internal.dynalink.support.LinkerServicesImpl;
1.14 import jdk.internal.dynalink.support.TypeConverterFactory;
1.15 +import jdk.internal.dynalink.support.TypeUtilities;
1.16
1.17 /**
1.18 * A factory class for creating {@link DynamicLinker}s. The most usual dynamic linker is a linker that is a composition
1.19 @@ -115,7 +117,6 @@
1.20 * @author Attila Szegedi
1.21 */
1.22 public class DynamicLinkerFactory {
1.23 -
1.24 /**
1.25 * Default value for {@link #setUnstableRelinkThreshold(int) unstable relink threshold}.
1.26 */
1.27 @@ -130,6 +131,7 @@
1.28 private boolean syncOnRelink = false;
1.29 private int unstableRelinkThreshold = DEFAULT_UNSTABLE_RELINK_THRESHOLD;
1.30 private GuardedInvocationFilter prelinkFilter;
1.31 + private MethodTypeConversionStrategy autoConversionStrategy;
1.32
1.33 /**
1.34 * Sets the class loader for automatic discovery of available linkers. If not set explicitly, then the thread
1.35 @@ -259,6 +261,29 @@
1.36 }
1.37
1.38 /**
1.39 + * Sets an object representing the conversion strategy for automatic type conversions. After
1.40 + * {@link TypeConverterFactory#asType(java.lang.invoke.MethodHandle, java.lang.invoke.MethodType)} has
1.41 + * applied all custom conversions to a method handle, it still needs to effect
1.42 + * {@link TypeUtilities#isMethodInvocationConvertible(Class, Class) method invocation conversions} that
1.43 + * can usually be automatically applied as per
1.44 + * {@link java.lang.invoke.MethodHandle#asType(java.lang.invoke.MethodType)}.
1.45 + * However, sometimes language runtimes will want to customize even those conversions for their own call
1.46 + * sites. A typical example is allowing unboxing of null return values, which is by default prohibited by
1.47 + * ordinary {@code MethodHandles.asType}. In this case, a language runtime can install its own custom
1.48 + * automatic conversion strategy, that can deal with null values. Note that when the strategy's
1.49 + * {@link MethodTypeConversionStrategy#asType(java.lang.invoke.MethodHandle, java.lang.invoke.MethodType)}
1.50 + * is invoked, the custom language conversions will already have been applied to the method handle, so by
1.51 + * design the difference between the handle's current method type and the desired final type will always
1.52 + * only be ones that can be subjected to method invocation conversions. The strategy also doesn't need to
1.53 + * invoke a final {@code MethodHandle.asType()} as the converter factory will do that as the final step.
1.54 + * @param autoConversionStrategy the strategy for applying method invocation conversions for the linker
1.55 + * created by this factory.
1.56 + */
1.57 + public void setAutoConversionStrategy(final MethodTypeConversionStrategy autoConversionStrategy) {
1.58 + this.autoConversionStrategy = autoConversionStrategy;
1.59 + }
1.60 +
1.61 + /**
1.62 * Creates a new dynamic linker consisting of all the prioritized, autodiscovered, and fallback linkers as well as
1.63 * the pre-link filter.
1.64 *
1.65 @@ -324,8 +349,9 @@
1.66 prelinkFilter = new DefaultPrelinkFilter();
1.67 }
1.68
1.69 - return new DynamicLinker(new LinkerServicesImpl(new TypeConverterFactory(typeConverters), composite),
1.70 - prelinkFilter, runtimeContextArgCount, syncOnRelink, unstableRelinkThreshold);
1.71 + return new DynamicLinker(new LinkerServicesImpl(new TypeConverterFactory(typeConverters,
1.72 + autoConversionStrategy), composite), prelinkFilter, runtimeContextArgCount, syncOnRelink,
1.73 + unstableRelinkThreshold);
1.74 }
1.75
1.76 private static ClassLoader getThreadContextClassLoader() {
