--- old/src/java.base/share/classes/java/lang/StringConcatHelper.java 2019-12-03 19:37:20.000000000 -0800 +++ new/src/java.base/share/classes/java/lang/StringConcatHelper.java 2019-12-03 19:37:20.000000000 -0800 @@ -28,6 +28,10 @@ import jdk.internal.misc.Unsafe; import jdk.internal.vm.annotation.ForceInline; +import java.lang.invoke.MethodHandle; +import java.lang.invoke.MethodHandles; +import java.lang.invoke.MethodType; + /** * Helper for string concatenation. These methods are mostly looked up with private lookups * from {@link java.lang.invoke.StringConcatFactory}, and used in {@link java.lang.invoke.MethodHandle} @@ -466,4 +470,13 @@ return String.COMPACT_STRINGS ? LATIN1 : UTF16; } + static MethodHandle lookupStatic(String name, MethodType methodType) { + try { + return MethodHandles.lookup().findStatic(StringConcatHelper.class, name, methodType); + } catch (NoSuchMethodException|IllegalAccessException e) { + throw new AssertionError(e); + } + } + + }