From 12e071db6034f80625f2b4d10e9e30a5fc6861f4 Mon Sep 17 00:00:00 2001
From: Ben Gruver <bgruv@google.com>
Date: Sun, 28 Oct 2012 13:13:11 -0700
Subject: [PATCH] Refactor how parameters/parameter names are handled

---
 .../DexBackedMethodImplementation.java        | 16 +++++++++++---
 .../dexlib2/dexbacked/util/DebugItemList.java | 21 ++++++-------------
 2 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/DexBackedMethodImplementation.java b/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/DexBackedMethodImplementation.java
index 107bf5be..9a13e5d5 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/DexBackedMethodImplementation.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/DexBackedMethodImplementation.java
@@ -112,7 +112,7 @@ public class DexBackedMethodImplementation implements MethodImplementation {
     public Iterable<? extends DebugItem> getDebugItems() {
         final int debugInfoOffset = dexBuf.readSmallUint(codeOffset + DEBUG_OFFSET_OFFSET);
         if (debugInfoOffset > 0) {
-            return new DebugItemList(dexBuf, debugInfoOffset, method);
+            return new DebugItemList(dexBuf, debugInfoOffset, this);
         }
         return ImmutableList.of();
     }
@@ -135,7 +135,9 @@ public class DexBackedMethodImplementation implements MethodImplementation {
         return ImmutableList.copyOf(instructions);
     }
 
-    public List<MethodParameter> getParametersWithNames() {
+    //TODO: reading the method params from the debug_info_item should probably be centralized with other debug stuff
+    @Nullable
+    public VariableSizeList<MethodParameter> getParametersWithNamesOrNull() {
         final int debugInfoOffset = dexBuf.readSmallUint(codeOffset + DEBUG_OFFSET_OFFSET);
         if (debugInfoOffset > 0) {
             DexReader reader = dexBuf.readerAt(debugInfoOffset);
@@ -168,6 +170,14 @@ public class DexBackedMethodImplementation implements MethodImplementation {
                 @Override public int size() { return methodParametersWithoutNames.size(); }
             };
         }
-        return ImmutableList.of();
+        return null;
+    }
+
+    public List<? extends MethodParameter> getParametersWithNames() {
+        List<MethodParameter> parameters = getParametersWithNamesOrNull();
+        if (parameters != null) {
+            return parameters;
+        }
+        return method.getParametersWithoutNames();
     }
 }
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/util/DebugItemList.java b/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/util/DebugItemList.java
index 146dc589..96066162 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/util/DebugItemList.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/util/DebugItemList.java
@@ -32,16 +32,14 @@
 package org.jf.dexlib2.dexbacked.util;
 
 import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.dexbacked.DexBackedMethodImplementation;
 import org.jf.dexlib2.dexbacked.DexBuffer;
 import org.jf.dexlib2.dexbacked.DexReader;
-import org.jf.dexlib2.iface.Method;
-import org.jf.dexlib2.iface.MethodImplementation;
 import org.jf.dexlib2.iface.MethodParameter;
 import org.jf.dexlib2.iface.debug.DebugItem;
 import org.jf.dexlib2.iface.debug.EndLocal;
 import org.jf.dexlib2.iface.debug.LocalInfo;
 import org.jf.dexlib2.immutable.debug.*;
-import org.jf.util.ExceptionWithContext;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -52,19 +50,13 @@ import java.util.NoSuchElementException;
 public class DebugItemList implements Iterable<DebugItem> {
     @Nonnull public final DexBuffer dexBuf;
     private final int debugInfoOffset;
-    @Nonnull private final Method method;
-    @Nonnull private final MethodImplementation methodImpl;
+    @Nonnull private final DexBackedMethodImplementation methodImpl;
 
     public DebugItemList(@Nonnull DexBuffer dexBuf,
                          int debugInfoOffset,
-                         @Nonnull Method method) {
+                         @Nonnull DexBackedMethodImplementation methodImpl) {
         this.dexBuf = dexBuf;
         this.debugInfoOffset = debugInfoOffset;
-        this.method = method;
-        MethodImplementation methodImpl = method.getImplementation();
-        if (methodImpl == null) {
-            throw new ExceptionWithContext("Creating a DebugItemList for a method with no implementation. WTF?");
-        }
         this.methodImpl = methodImpl;
     }
 
@@ -86,10 +78,9 @@ public class DebugItemList implements Iterable<DebugItem> {
         final LocalInfo[] locals = new LocalInfo[registerCount];
         Arrays.fill(locals, EMPTY_LOCAL_INFO);
 
-        // getParameters returns a VariableSizeList when a method implementation is present. Since we're reading debug
-        // information, the method obviously has an implementation.
-        VariableSizeList<? extends MethodParameter> parameters =
-                (VariableSizeList<? extends MethodParameter>)method.getParameters();
+        // getParametersWithNames returns a VariableSizeList when debug info is present
+        VariableSizeList<? extends MethodParameter> parameters = methodImpl.getParametersWithNamesOrNull();
+        assert parameters != null;
         final VariableSizeList<? extends MethodParameter>.Iterator parameterIterator = parameters.listIterator();
 
         { // local scope for i