Handle removed/changed fields in DMH

In case matching field is not found, clear (set to null) references to faulty DMH.
Long term, should replace such DMH's with instances that will throw more meaningful
error messages at runtime.

2 files changed, 103 insertions, 30 deletions

diff --git a/dcevm/src/test/java7/com/github/dcevm/test/fields/InstanceFieldHandleTest.java b/dcevm/src/test/java7/com/github/dcevm/test/fields/InstanceFieldHandleTest.java
index 48f3f46f..4253c3b8 100644
--- a/dcevm/src/test/java7/com/github/dcevm/test/fields/InstanceFieldHandleTest.java
+++ b/dcevm/src/test/java7/com/github/dcevm/test/fields/InstanceFieldHandleTest.java
@@ -24,8 +24,8 @@
 package com.github.dcevm.test.fields;
 
 import org.junit.After;
+import org.junit.Assert;
 import org.junit.Before;
-import org.junit.Ignore;
 import org.junit.Test;
 
 import java.lang.invoke.MethodHandle;
@@ -45,13 +45,21 @@ public class InstanceFieldHandleTest {
   public static class A {
     public int fieldA;
     public int fieldB;
+
+    public int getFieldA() {
+      return -1;
+    }
   }
 
   // Version 1 (fields swapped and new one is added)
   public static class A___1 {
-    public String fieldC;
     public int fieldB;
     public int fieldA;
+    public String fieldC;
+
+    public int getFieldA() {
+      return fieldA;
+    }
   }
 
   // Version 2 (fields removed)
@@ -73,41 +81,72 @@ public class InstanceFieldHandleTest {
   @Test
   public void testFieldChangeOrder() throws Throwable {
     A a = new A();
-    MethodHandle handle = MethodHandles.publicLookup().findGetter(A.class, "fieldA", int.class);
+    MethodHandle getter = MethodHandles.publicLookup().findGetter(A.class, "fieldA", int.class);
+    MethodHandle setter = MethodHandles.publicLookup().findSetter(A.class, "fieldA", int.class);
 
     a.fieldA = 3;
-    assertEquals(3, handle.invoke(a));
+    assertEquals(3, getter.invoke(a));
 
     // Swap fields
     __toVersion__(1);
-    assertEquals(3, handle.invoke(a));
+
+    assertEquals(3, getter.invoke(a));
+    setter.invoke(a, 53);
+    assertEquals(53, a.getFieldA());
+    assertEquals(53, getter.invoke(a));
   }
 
   @Test
-  @Ignore
-  public void testStaticFieldRemoved() throws Throwable {
-    MethodHandle handle = MethodHandles.publicLookup().findGetter(A.class, "fieldA", int.class);
+  public void testFieldRemoved() throws Throwable {
     A a = new A();
+    MethodHandle getter = MethodHandles.publicLookup().findGetter(A.class, "fieldA", int.class);
+    MethodHandle setter = MethodHandles.publicLookup().findSetter(A.class, "fieldA", int.class);
+
     a.fieldA = 3;
-    assertEquals(3, handle.invoke(a));
+    assertEquals(3, getter.invoke(a));
 
     // Remove fieldA
     __toVersion__(2);
 
-    handle.invoke(a);
+    try {
+      getter.invoke(a);
+      Assert.fail("Handle should have been cleared!");
+    } catch (NullPointerException e) {
+      // Handle was cleared!
+    }
+
+    try {
+      setter.invoke(a, 10);
+      Assert.fail("Handle should have been cleared!");
+    } catch (NullPointerException e) {
+      // Handle was cleared!
+    }
   }
 
   @Test
-  @Ignore
-  public void testStaticFieldTypeChange() throws Throwable {
-    MethodHandle handle = MethodHandles.publicLookup().findGetter(A.class, "fieldA", int.class);
+  public void testFieldTypeChange() throws Throwable {
     A a = new A();
+    MethodHandle getter = MethodHandles.publicLookup().findGetter(A.class, "fieldA", int.class);
+    MethodHandle setter = MethodHandles.publicLookup().findSetter(A.class, "fieldA", int.class);
+
     a.fieldA = 3;
-    assertEquals(3, handle.invoke(a));
+    assertEquals(3, getter.invoke(a));
 
     // Remove fieldA
     __toVersion__(3);
 
-    handle.invoke(a);
+    try {
+      getter.invoke(a);
+      Assert.fail("Handle should have been cleared!");
+    } catch (NullPointerException e) {
+      // Handle was cleared!
+    }
+
+    try {
+      setter.invoke(a, 10);
+      Assert.fail("Handle should have been cleared!");
+    } catch (NullPointerException e) {
+      // Handle was cleared!
+    }
   }
 }
\ No newline at end of file
diff --git a/dcevm/src/test/java7/com/github/dcevm/test/fields/StaticFieldHandleTest.java b/dcevm/src/test/java7/com/github/dcevm/test/fields/StaticFieldHandleTest.java
index 6f565252..237cff25 100644
--- a/dcevm/src/test/java7/com/github/dcevm/test/fields/StaticFieldHandleTest.java
+++ b/dcevm/src/test/java7/com/github/dcevm/test/fields/StaticFieldHandleTest.java
@@ -23,19 +23,15 @@
  */
 package com.github.dcevm.test.fields;
 
-import com.github.dcevm.test.TestUtil;
 import org.junit.After;
 import org.junit.Assert;
 import org.junit.Before;
-import org.junit.Ignore;
 import org.junit.Test;
 
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
-import java.lang.invoke.MethodType;
 
 import static com.github.dcevm.test.util.HotSwapTestHelper.__toVersion__;
-import static com.github.dcevm.test.util.HotSwapTestHelper.__version__;
 import static org.junit.Assert.assertEquals;
 
 /**
@@ -49,12 +45,21 @@ public class StaticFieldHandleTest {
   public static class A {
     public static int fieldA;
     public static int fieldB;
+
+    public static int getFieldA() {
+      return -1;
+    }
   }
 
   // Version 1 (fields swapped)
   public static class A___1 {
     public static int fieldB;
     public static int fieldA;
+    public static String fieldC;
+
+    public static int getFieldA() {
+      return fieldA;
+    }
   }
 
   // Version 2 (fields removed)
@@ -75,44 +80,73 @@ public class StaticFieldHandleTest {
 
   @Test
   public void testStaticFieldChangeOrder() throws Throwable {
-    MethodHandle handle = MethodHandles.publicLookup().findStaticGetter(A.class, "fieldA", int.class);
+    MethodHandle getter = MethodHandles.publicLookup().findStaticGetter(A.class, "fieldA", int.class);
+    MethodHandle setter = MethodHandles.publicLookup().findStaticSetter(A.class, "fieldA", int.class);
 
     A.fieldA = 3;
     A.fieldB = 5;
-    assertEquals(3, handle.invoke());
+    assertEquals(3, getter.invoke());
 
     // Swap fields A and B
     __toVersion__(1);
-    assertEquals(3, handle.invoke());
+
+    assertEquals(3, getter.invoke());
+    setter.invoke(12);
+    assertEquals(12, A.getFieldA());
+    assertEquals(12, getter.invoke());
   }
 
   @Test
-  @Ignore
   public void testStaticFieldRemoved() throws Throwable {
-    MethodHandle handle = MethodHandles.publicLookup().findStaticGetter(A.class, "fieldA", int.class);
+    MethodHandle getter = MethodHandles.publicLookup().findStaticGetter(A.class, "fieldA", int.class);
+    MethodHandle setter = MethodHandles.publicLookup().findStaticSetter(A.class, "fieldA", int.class);
 
     A.fieldA = 3;
     A.fieldB = 5;
-    assertEquals(3, handle.invoke());
+    assertEquals(3, getter.invoke());
 
     // Remove fieldA
     __toVersion__(2);
 
-    handle.invoke();
+    try {
+      getter.invoke();
+      Assert.fail("Handle should have been cleared!");
+    } catch (NullPointerException e) {
+      // Handle was cleared!
+    }
+
+    try {
+      setter.invoke(15);
+      Assert.fail("Handle should have been cleared!");
+    } catch (NullPointerException e) {
+      // Handle was cleared!
+    }
   }
 
   @Test
-  @Ignore
   public void testStaticFieldTypeChange() throws Throwable {
-    MethodHandle handle = MethodHandles.publicLookup().findStaticGetter(A.class, "fieldA", int.class);
+    MethodHandle getter = MethodHandles.publicLookup().findStaticGetter(A.class, "fieldA", int.class);
+    MethodHandle setter = MethodHandles.publicLookup().findStaticSetter(A.class, "fieldA", int.class);
 
     A.fieldA = 3;
     A.fieldB = 5;
-    assertEquals(3, handle.invoke());
+    assertEquals(3, getter.invoke());
 
     // Remove fieldA
     __toVersion__(3);
 
-    handle.invoke();
+    try {
+      getter.invoke();
+      Assert.fail("Handle should have been cleared!");
+    } catch (NullPointerException e) {
+      // Handle was cleared!
+    }
+
+    try {
+      setter.invoke(15);
+      Assert.fail("Handle should have been cleared!");
+    } catch (NullPointerException e) {
+      // Handle was cleared!
+    }
   }
 }
\ No newline at end of file