test/java/lang/invoke/JavaDocExamplesTest.java

*** 1,7 ****
  /*
!  * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
--- 1,7 ----
  /*
!  * Copyright (c) 2009, 2016, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
*** 55,65 ****
--- 55,67 ----
          testFindStatic();
          testFindConstructor();
          testFindVirtual();
          testFindSpecial();
          testPermuteArguments();
+         testZero();
          testDropArguments();
+         testDropArgumentsToMatch();
          testFilterArguments();
          testFoldArguments();
          testFoldArguments2();
          testMethodHandlesSummary();
          testAsSpreader();
*** 233,242 ****
--- 235,255 ----
  MethodHandle d12 = dropArguments(cat, 1, int.class, boolean.class);
  assertEquals("xz", (String) d12.invokeExact("x", 12, true, "z"));
              }}
      }
  
+ @Test public void testZero() throws Throwable {
+         {{
+ {} /// JAVADOC
+ Class<?> type = Double.class;
+ MethodHandle mh1 = MethodHandles.explicitCastArguments(MethodHandles.constant(Object.class, null), methodType(type));
+ assertEquals("()Double", mh1.type().toString());
+ MethodHandle mh2 = MethodHandles.empty(methodType(type));
+ assertEquals("()Double", mh2.type().toString()); 
+         }}
+    }
+ 
      @Test public void testDropArguments() throws Throwable {
          {{
  {} /// JAVADOC
  MethodHandle cat = lookup().findVirtual(String.class,
    "concat", methodType(String.class, String.class));
*** 260,269 ****
--- 273,300 ----
  MethodHandle d12 = dropArguments(cat, 1, int.class, boolean.class);
  assertEquals("xz", (String) d12.invokeExact("x", 12, true, "z"));
              }}
      }
  
+     @Test public void testDropArgumentsToMatch() throws Throwable {
+         {{
+ {} /// JAVADOC
+ MethodHandle h0= constant(boolean.class, true);
+ MethodHandle h1 = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class));
+ MethodType bigType = h1.type().insertParameterTypes(1, String.class, int.class);
+ MethodHandle h2 = dropArguments(h1, 0, bigType.parameterList());
+ if (h1.type().parameterCount() < h2.type().parameterCount()) {
+     h1 = dropArgumentsToMatch(h1, 0, h2.type().parameterList(), 0);  // lengthen h1
+ }
+ else {
+     h2 = dropArgumentsToMatch(h2, 0, h1.type().parameterList(), 0);    // lengthen h2
+ }
+ MethodHandle h3 = guardWithTest(h0, h1, h2);
+ assertEquals("xy", h3.invoke("x", "y", 1, "a", "b", "c"));
+         }}
+     }
+ 
      @Test public void testFilterArguments() throws Throwable {
          {{
  {} /// JAVADOC
  MethodHandle cat = lookup().findVirtual(String.class,
    "concat", methodType(String.class, String.class));