Make smali respect order of implements

Previously smali would reorder implements directives to be
alphabetical in the dex file. In the Java 8 Language the order of
interfaces may affect the order of initializer invocation when using
default methods. Therefore we will preserve this order in
smali/baksmai.

Bug: 24338722

Change-Id: I6851b02a5402c7d4cd4b60af54052c320e48d0bf

15 files changed, 129 insertions, 57 deletions

diff --git a/baksmali/src/main/java/org/jf/baksmali/Adaptors/ClassDefinition.java b/baksmali/src/main/java/org/jf/baksmali/Adaptors/ClassDefinition.java
index 9c171f49..2529af8a 100644
--- a/baksmali/src/main/java/org/jf/baksmali/Adaptors/ClassDefinition.java
+++ b/baksmali/src/main/java/org/jf/baksmali/Adaptors/ClassDefinition.java
@@ -146,8 +146,7 @@ public class ClassDefinition {
     }
 
     private void writeInterfaces(IndentingWriter writer) throws IOException {
-        List<String> interfaces = Lists.newArrayList(classDef.getInterfaces());
-        Collections.sort(interfaces);
+        List<String> interfaces = classDef.getInterfaces();
 
         if (interfaces.size() != 0) {
             writer.write('\n');
diff --git a/baksmali/src/test/java/org/jf/baksmali/InterfaceOrderTest.java b/baksmali/src/test/java/org/jf/baksmali/InterfaceOrderTest.java
new file mode 100644
index 00000000..d85d7913
--- /dev/null
+++ b/baksmali/src/test/java/org/jf/baksmali/InterfaceOrderTest.java
@@ -0,0 +1,41 @@
+/*
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.jf.baksmali;
+
+import org.junit.Test;
+
+public class InterfaceOrderTest extends IdenticalRoundtripTest {
+    @Test
+    public void testInterfaceOrder() {
+        runTest("InterfaceOrder", new baksmaliOptions());
+    }
+}
diff --git a/baksmali/src/test/resources/InterfaceOrderTest/InterfaceOrder.smali b/baksmali/src/test/resources/InterfaceOrderTest/InterfaceOrder.smali
new file mode 100644
index 00000000..b4745cb3
--- /dev/null
+++ b/baksmali/src/test/resources/InterfaceOrderTest/InterfaceOrder.smali
@@ -0,0 +1,37 @@
+.class public LInterfaceOrder;
+.super Ljava/lang/Object;
+
+# Note how these two interfaces are not in alphabetical order
+.implements Ljava/io/Serializable;
+.implements Ljava/util/EventListener;
+.implements Ljava/lang/Runnable;
+.implements Ljava/io/Flushable;
+.implements Ljava/lang/Clonable;
+.implements Ljava/util/Observer;
+.implements Ljava/io/Closeable;
+
+# direct methods
+.method public constructor <init>()V
+    .registers 1
+    return-void
+.end method
+
+.method public close()V
+    .registers 1
+    return-void
+.end method
+
+.method public flush()V
+    .registers 1
+    return-void
+.end method
+
+.method public run()V
+    .registers 1
+    return-void
+.end method
+
+.method public update(Ljava/util/Observable;Ljava/lang/Object;)V
+    .registers 3
+    return-void
+.end method
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/analysis/reflection/ReflectionClassDef.java b/dexlib2/src/main/java/org/jf/dexlib2/analysis/reflection/ReflectionClassDef.java
index fc1dc62f..7e8a2829 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/analysis/reflection/ReflectionClassDef.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/analysis/reflection/ReflectionClassDef.java
@@ -33,6 +33,7 @@ package org.jf.dexlib2.analysis.reflection;
 
 import com.google.common.base.Function;
 import com.google.common.base.Predicate;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterators;
 import org.jf.dexlib2.analysis.reflection.util.ReflectionUtils;
@@ -48,6 +49,7 @@ import java.lang.reflect.Constructor;
 import java.lang.reflect.Modifier;
 import java.util.AbstractSet;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Set;
 
 /**
@@ -78,23 +80,17 @@ public class ReflectionClassDef extends BaseTypeReference implements ClassDef {
         return ReflectionUtils.javaToDexName(superClass.getName());
     }
 
-    @Nonnull @Override public Set<String> getInterfaces() {
-        return new AbstractSet<String>() {
-            @Nonnull @Override public Iterator<String> iterator() {
-                return Iterators.transform(Iterators.forArray(cls.getInterfaces()), new Function<Class, String>() {
-                    @Nullable @Override public String apply(@Nullable Class input) {
-                        if (input == null) {
-                            return null;
-                        }
-                        return ReflectionUtils.javaToDexName(input.getName());
-                    }
-                });
+    @Nonnull @Override public List<String> getInterfaces() {
+        return ImmutableList.copyOf(Iterators.transform(Iterators.forArray(cls.getInterfaces()), new Function<Class, String>() {
+            @Nullable
+            @Override
+            public String apply(@Nullable Class input) {
+                if (input == null) {
+                    return null;
+                }
+                return ReflectionUtils.javaToDexName(input.getName());
             }
-
-            @Override public int size() {
-                return cls.getInterfaces().length;
-            }
-        };
+        }));
     }
 
     @Nullable @Override public String getSourceFile() {
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/DexBackedClassDef.java b/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/DexBackedClassDef.java
index 9596a278..88f1dce9 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/DexBackedClassDef.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/dexbacked/DexBackedClassDef.java
@@ -31,6 +31,7 @@
 
 package org.jf.dexlib2.dexbacked;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import org.jf.dexlib2.base.reference.BaseTypeReference;
@@ -47,7 +48,9 @@ import org.jf.dexlib2.immutable.reference.ImmutableMethodReference;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
+import java.util.AbstractList;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Set;
 
 public class DexBackedClassDef extends BaseTypeReference implements ClassDef {
@@ -114,21 +117,21 @@ public class DexBackedClassDef extends BaseTypeReference implements ClassDef {
 
     @Nonnull
     @Override
-    public Set<String> getInterfaces() {
+    public List<String> getInterfaces() {
         final int interfacesOffset = dexFile.readSmallUint(classDefOffset + ClassDefItem.INTERFACES_OFFSET);
         if (interfacesOffset > 0) {
             final int size = dexFile.readSmallUint(interfacesOffset);
-            return new FixedSizeSet<String>() {
-                @Nonnull
+            return new AbstractList<String>() {
                 @Override
-                public String readItem(int index) {
+                @Nonnull
+                public String get(int index) {
                     return dexFile.getType(dexFile.readUshort(interfacesOffset + 4 + (2*index)));
                 }
 
                 @Override public int size() { return size; }
             };
         }
-        return ImmutableSet.of();
+        return ImmutableList.of();
     }
 
     @Nonnull
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/iface/ClassDef.java b/dexlib2/src/main/java/org/jf/dexlib2/iface/ClassDef.java
index 31d7fb99..78e17b15 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/iface/ClassDef.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/iface/ClassDef.java
@@ -35,6 +35,7 @@ import org.jf.dexlib2.iface.reference.TypeReference;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
+import java.util.List;
 import java.util.Set;
 
 /**
@@ -72,11 +73,11 @@ public interface ClassDef extends TypeReference, Annotatable {
     @Nullable String getSuperclass();
 
     /**
-     * Gets a set of the interfaces that this class implements.
+     * Gets a list of the interfaces that this class implements.
      *
-     * @return A set of the interfaces that this class implements
+     * @return A list of the interfaces that this class implements
      */
-    @Nonnull Set<String> getInterfaces();
+    @Nonnull List<String> getInterfaces();
 
     /**
      * Gets the name of the primary source file that this class is defined in, if available.
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/immutable/ImmutableClassDef.java b/dexlib2/src/main/java/org/jf/dexlib2/immutable/ImmutableClassDef.java
index 42e14549..8bdfff26 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/immutable/ImmutableClassDef.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/immutable/ImmutableClassDef.java
@@ -47,12 +47,13 @@ import javax.annotation.Nullable;
 import java.util.AbstractCollection;
 import java.util.Collection;
 import java.util.Iterator;
+import java.util.List;
 
 public class ImmutableClassDef extends BaseTypeReference implements ClassDef {
     @Nonnull protected final String type;
     protected final int accessFlags;
     @Nullable protected final String superclass;
-    @Nonnull protected final ImmutableSet<String> interfaces;
+    @Nonnull protected final ImmutableList<String> interfaces;
     @Nullable protected final String sourceFile;
     @Nonnull protected final ImmutableSet<? extends ImmutableAnnotation> annotations;
     @Nonnull protected final ImmutableSortedSet<? extends ImmutableField> staticFields;
@@ -78,7 +79,7 @@ public class ImmutableClassDef extends BaseTypeReference implements ClassDef {
         this.type = type;
         this.accessFlags = accessFlags;
         this.superclass = superclass;
-        this.interfaces = interfaces==null ? ImmutableSet.<String>of() : ImmutableSet.copyOf(interfaces);
+        this.interfaces = interfaces==null ? ImmutableList.<String>of() : ImmutableList.copyOf(interfaces);
         this.sourceFile = sourceFile;
         this.annotations = ImmutableAnnotation.immutableSetOf(annotations);
         this.staticFields = ImmutableField.immutableSetOf(Iterables.filter(fields, FieldUtil.FIELD_IS_STATIC));
@@ -100,7 +101,7 @@ public class ImmutableClassDef extends BaseTypeReference implements ClassDef {
         this.type = type;
         this.accessFlags = accessFlags;
         this.superclass = superclass;
-        this.interfaces = interfaces==null ? ImmutableSet.<String>of() : ImmutableSet.copyOf(interfaces);
+        this.interfaces = interfaces==null ? ImmutableList.<String>of() : ImmutableList.copyOf(interfaces);
         this.sourceFile = sourceFile;
         this.annotations = ImmutableAnnotation.immutableSetOf(annotations);
         this.staticFields = ImmutableField.immutableSetOf(staticFields);
@@ -112,7 +113,7 @@ public class ImmutableClassDef extends BaseTypeReference implements ClassDef {
     public ImmutableClassDef(@Nonnull String type,
                              int accessFlags,
                              @Nullable String superclass,
-                             @Nullable ImmutableSet<String> interfaces,
+                             @Nullable ImmutableList<String> interfaces,
                              @Nullable String sourceFile,
                              @Nullable ImmutableSet<? extends ImmutableAnnotation> annotations,
                              @Nullable ImmutableSortedSet<? extends ImmutableField> staticFields,
@@ -122,7 +123,7 @@ public class ImmutableClassDef extends BaseTypeReference implements ClassDef {
         this.type = type;
         this.accessFlags = accessFlags;
         this.superclass = superclass;
-        this.interfaces = ImmutableUtils.nullToEmptySet(interfaces);
+        this.interfaces = ImmutableUtils.nullToEmptyList(interfaces);
         this.sourceFile = sourceFile;
         this.annotations = ImmutableUtils.nullToEmptySet(annotations);
         this.staticFields = ImmutableUtils.nullToEmptySortedSet(staticFields);
@@ -151,7 +152,7 @@ public class ImmutableClassDef extends BaseTypeReference implements ClassDef {
     @Nonnull @Override public String getType() { return type; }
     @Override public int getAccessFlags() { return accessFlags; }
     @Nullable @Override public String getSuperclass() { return superclass; }
-    @Nonnull @Override public ImmutableSet<String> getInterfaces() { return interfaces; }
+    @Nonnull @Override public ImmutableList<String> getInterfaces() { return interfaces; }
     @Nullable @Override public String getSourceFile() { return sourceFile; }
     @Nonnull @Override public ImmutableSet<? extends ImmutableAnnotation> getAnnotations() { return annotations; }
     @Nonnull @Override public ImmutableSet<? extends ImmutableField> getStaticFields() { return staticFields; }
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/rewriter/ClassDefRewriter.java b/dexlib2/src/main/java/org/jf/dexlib2/rewriter/ClassDefRewriter.java
index ad246e5b..7e34ee33 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/rewriter/ClassDefRewriter.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/rewriter/ClassDefRewriter.java
@@ -41,6 +41,7 @@ import org.jf.dexlib2.iface.Method;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Set;
 
 public class ClassDefRewriter implements Rewriter<ClassDef> {
@@ -73,8 +74,8 @@ public class ClassDefRewriter implements Rewriter<ClassDef> {
             return RewriterUtils.rewriteNullable(rewriters.getTypeRewriter(), classDef.getSuperclass());
         }
 
-        @Override @Nonnull public Set<String> getInterfaces() {
-            return RewriterUtils.rewriteSet(rewriters.getTypeRewriter(), classDef.getInterfaces());
+        @Override @Nonnull public List<String> getInterfaces() {
+            return RewriterUtils.rewriteList(rewriters.getTypeRewriter(), classDef.getInterfaces());
         }
 
         @Override @Nullable public String getSourceFile() {
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/ClassSection.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/ClassSection.java
index bb2e4a72..d28dd444 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/ClassSection.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/ClassSection.java
@@ -53,7 +53,7 @@ public interface ClassSection<StringKey extends CharSequence, TypeKey extends Ch
     @Nonnull TypeKey getType(@Nonnull ClassKey key);
     int getAccessFlags(@Nonnull ClassKey key);
     @Nullable TypeKey getSuperclass(@Nonnull ClassKey key);
-    @Nullable TypeListKey getSortedInterfaces(@Nonnull ClassKey key);
+    @Nullable TypeListKey getInterfaces(@Nonnull ClassKey key);
     @Nullable StringKey getSourceFile(@Nonnull ClassKey key);
     @Nullable Collection<? extends EncodedValue> getStaticInitializers(@Nonnull ClassKey key);
 
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java
index 916147ec..be23978e 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java
@@ -433,7 +433,7 @@ public abstract class DexWriter<
         nextIndex = writeClass(indexWriter, offsetWriter, nextIndex, superEntry);
 
         // then, try to write interfaces
-        for (TypeKey interfaceTypeKey: typeListSection.getTypes(classSection.getSortedInterfaces(key))) {
+        for (TypeKey interfaceTypeKey: typeListSection.getTypes(classSection.getInterfaces(key))) {
             Map.Entry<? extends ClassKey, Integer> interfaceEntry = classSection.getClassEntryByType(interfaceTypeKey);
             nextIndex = writeClass(indexWriter, offsetWriter, nextIndex, interfaceEntry);
         }
@@ -446,7 +446,7 @@ public abstract class DexWriter<
         indexWriter.writeInt(typeSection.getItemIndex(classSection.getType(key)));
         indexWriter.writeInt(classSection.getAccessFlags(key));
         indexWriter.writeInt(typeSection.getNullableItemIndex(classSection.getSuperclass(key)));
-        indexWriter.writeInt(typeListSection.getNullableItemOffset(classSection.getSortedInterfaces(key)));
+        indexWriter.writeInt(typeListSection.getNullableItemOffset(classSection.getInterfaces(key)));
         indexWriter.writeInt(stringSection.getNullableItemIndex(classSection.getSourceFile(key)));
         indexWriter.writeInt(classSection.getAnnotationDirectoryOffset(key));
 
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderClassDef.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderClassDef.java
index f19a2e7f..10215925 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderClassDef.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderClassDef.java
@@ -31,6 +31,7 @@
 
 package org.jf.dexlib2.writer.builder;
 
+import com.google.common.base.Function;
 import com.google.common.base.Functions;
 import com.google.common.collect.*;
 import org.jf.dexlib2.base.reference.BaseTypeReference;
@@ -101,16 +102,8 @@ public class BuilderClassDef extends BaseTypeReference implements ClassDef {
     @Nonnull @Override public SortedSet<BuilderMethod> getVirtualMethods() { return virtualMethods; }
 
     @Nonnull @Override
-    public Set<String> getInterfaces() {
-        return new AbstractSet<String>() {
-            @Nonnull @Override public Iterator<String> iterator() {
-                return Iterators.transform(interfaces.iterator(), Functions.toStringFunction());
-            }
-
-            @Override public int size() {
-                return interfaces.size();
-            }
-        };
+    public List<String> getInterfaces() {
+        return Lists.transform(this.interfaces, Functions.toStringFunction());
     }
 
     @Nonnull @Override public Collection<BuilderField> getFields() {
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderClassPool.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderClassPool.java
index 76fb9e03..695109fa 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderClassPool.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderClassPool.java
@@ -122,7 +122,7 @@ public class BuilderClassPool implements ClassSection<BuilderStringReference, Bu
         return builderClassDef.superclass;
     }
 
-    @Nullable @Override public BuilderTypeList getSortedInterfaces(@Nonnull BuilderClassDef builderClassDef) {
+    @Nullable @Override public BuilderTypeList getInterfaces(@Nonnull BuilderClassDef builderClassDef) {
         return builderClassDef.interfaces;
     }
 
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/DexBuilder.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/DexBuilder.java
index 469a3324..9a727b27 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/DexBuilder.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/DexBuilder.java
@@ -35,6 +35,7 @@ import com.google.common.base.Function;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterators;
 import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
 import org.jf.dexlib2.ValueType;
 import org.jf.dexlib2.iface.Annotation;
 import org.jf.dexlib2.iface.MethodImplementation;
@@ -117,16 +118,15 @@ public class DexBuilder extends DexWriter<BuilderStringReference, BuilderStringR
         if (interfaces == null) {
             interfaces = ImmutableList.of();
         } else {
-            interfaces = Lists.newArrayList(interfaces);
-            Collections.sort(interfaces);
-            String prev = null;
+            Set<String> interfaces_copy = Sets.newHashSet(interfaces);
             Iterator<String> interfaceIterator = interfaces.iterator();
             while (interfaceIterator.hasNext()) {
                 String iface = interfaceIterator.next();
-                if (prev != null && iface.equals(prev)) {
+                if (!interfaces_copy.contains(iface)) {
                     interfaceIterator.remove();
+                } else {
+                    interfaces_copy.remove(iface);
                 }
-                prev = iface;
             }
         }
 
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/ClassPool.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/ClassPool.java
index f2440cdb..25cf4da8 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/ClassPool.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/ClassPool.java
@@ -250,7 +250,7 @@ public class ClassPool implements ClassSection<CharSequence, CharSequence,
         return classDef.getSuperclass();
     }
 
-    @Nullable @Override public TypeListPool.Key<SortedSet<String>> getSortedInterfaces(@Nonnull PoolClassDef classDef) {
+    @Nullable @Override public TypeListPool.Key<List<String>> getInterfaces(@Nonnull PoolClassDef classDef) {
         return classDef.interfaces;
     }
 
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/PoolClassDef.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/PoolClassDef.java
index fe897d26..00958fb8 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/PoolClassDef.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/PoolClassDef.java
@@ -43,7 +43,7 @@ import java.util.*;
 
 class PoolClassDef extends BaseTypeReference implements ClassDef {
     @Nonnull final ClassDef classDef;
-    @Nonnull final TypeListPool.Key<SortedSet<String>> interfaces;
+    @Nonnull final TypeListPool.Key<List<String>> interfaces;
     @Nonnull final ImmutableSortedSet<Field> staticFields;
     @Nonnull final ImmutableSortedSet<Field> instanceFields;
     @Nonnull final ImmutableSortedSet<PoolMethod> directMethods;
@@ -56,7 +56,7 @@ class PoolClassDef extends BaseTypeReference implements ClassDef {
     PoolClassDef(@Nonnull ClassDef classDef) {
         this.classDef = classDef;
 
-        interfaces = new TypeListPool.Key<SortedSet<String>>(ImmutableSortedSet.copyOf(classDef.getInterfaces()));
+        interfaces = new TypeListPool.Key<List<String>>(ImmutableList.copyOf(classDef.getInterfaces()));
         staticFields = ImmutableSortedSet.copyOf(classDef.getStaticFields());
         instanceFields = ImmutableSortedSet.copyOf(classDef.getInstanceFields());
         directMethods = ImmutableSortedSet.copyOf(
@@ -77,7 +77,7 @@ class PoolClassDef extends BaseTypeReference implements ClassDef {
         return classDef.getSuperclass();
     }
 
-    @Nonnull @Override public SortedSet<String> getInterfaces() {
+    @Nonnull @Override public List<String> getInterfaces() {
         return interfaces.types;
     }