diff --git a/dexlib2/src/main/java/org/jf/dexlib2/iface/debug/SetSourceFile.java b/dexlib2/src/main/java/org/jf/dexlib2/iface/debug/SetSourceFile.java
index d992423d..de243abc 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/iface/debug/SetSourceFile.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/iface/debug/SetSourceFile.java
@@ -31,8 +31,11 @@
 
 package org.jf.dexlib2.iface.debug;
 
+import org.jf.dexlib2.iface.reference.StringReference;
+
 import javax.annotation.Nullable;
 
 public interface SetSourceFile extends DebugItem {
     @Nullable String getSourceFile();
+    @Nullable StringReference getSourceFileReference();
 }
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/iface/debug/StartLocal.java b/dexlib2/src/main/java/org/jf/dexlib2/iface/debug/StartLocal.java
index 01ec1e09..90a55475 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/iface/debug/StartLocal.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/iface/debug/StartLocal.java
@@ -31,6 +31,15 @@
 
 package org.jf.dexlib2.iface.debug;
 
+import org.jf.dexlib2.iface.reference.StringReference;
+import org.jf.dexlib2.iface.reference.TypeReference;
+
+import javax.annotation.Nullable;
+
 public interface StartLocal extends DebugItem, LocalInfo {
     int getRegister();
+
+    @Nullable StringReference getNameReference();
+    @Nullable TypeReference getTypeReference();
+    @Nullable StringReference getSignatureReference();
 }
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/immutable/debug/ImmutableSetSourceFile.java b/dexlib2/src/main/java/org/jf/dexlib2/immutable/debug/ImmutableSetSourceFile.java
index 54d7e29c..b74adab0 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/immutable/debug/ImmutableSetSourceFile.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/immutable/debug/ImmutableSetSourceFile.java
@@ -32,7 +32,9 @@
 package org.jf.dexlib2.immutable.debug;
 
 import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.base.reference.BaseStringReference;
 import org.jf.dexlib2.iface.debug.SetSourceFile;
+import org.jf.dexlib2.iface.reference.StringReference;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -58,5 +60,14 @@ public class ImmutableSetSourceFile extends ImmutableDebugItem implements SetSou
 
     @Nullable @Override public String getSourceFile() { return sourceFile; }
 
+    @Nullable @Override public StringReference getSourceFileReference() {
+        return sourceFile==null?null:new BaseStringReference() {
+            @Nonnull @Override public String getString() {
+                return sourceFile;
+            }
+        };
+    }
+
+
     @Override public int getDebugItemType() { return DebugItemType.SET_SOURCE_FILE; }
 }
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/immutable/debug/ImmutableStartLocal.java b/dexlib2/src/main/java/org/jf/dexlib2/immutable/debug/ImmutableStartLocal.java
index 24eb7c83..635e92ad 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/immutable/debug/ImmutableStartLocal.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/immutable/debug/ImmutableStartLocal.java
@@ -32,7 +32,11 @@
 package org.jf.dexlib2.immutable.debug;
 
 import org.jf.dexlib2.DebugItemType;
+import org.jf.dexlib2.base.reference.BaseStringReference;
+import org.jf.dexlib2.base.reference.BaseTypeReference;
 import org.jf.dexlib2.iface.debug.StartLocal;
+import org.jf.dexlib2.iface.reference.StringReference;
+import org.jf.dexlib2.iface.reference.TypeReference;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -69,6 +73,31 @@ public class ImmutableStartLocal extends ImmutableDebugItem implements StartLoca
     }
 
     @Override public int getRegister() { return register; }
+
+    @Nullable @Override public StringReference getNameReference() {
+        return name==null?null:new BaseStringReference() {
+            @Nonnull @Override public String getString() {
+                return name;
+            }
+        };
+    }
+
+    @Nullable @Override public TypeReference getTypeReference() {
+        return type==null?null:new BaseTypeReference() {
+            @Nonnull @Override public String getType() {
+                return type;
+            }
+        };
+    }
+
+    @Nullable @Override public StringReference getSignatureReference() {
+        return signature==null?null:new BaseStringReference() {
+            @Nonnull @Override public String getString() {
+                return signature;
+            }
+        };
+    }
+
     @Nullable @Override public String getName() { return name; }
     @Nullable @Override public String getType() { return type; }
     @Nullable @Override public String getSignature() { return signature; }
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 c41b17e0..a57904ea 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/ClassSection.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/ClassSection.java
@@ -32,6 +32,7 @@
 package org.jf.dexlib2.writer;
 
 import org.jf.dexlib2.iface.TryBlock;
+import org.jf.dexlib2.iface.debug.DebugItem;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -41,7 +42,7 @@ import java.util.List;
 import java.util.Map;
 
 public interface ClassSection<StringKey extends CharSequence, TypeKey extends CharSequence, TypeListKey, ClassKey,
-        FieldKey, MethodKey, AnnotationSetKey, EncodedValue, DebugItem, Insn,
+        FieldKey, MethodKey, AnnotationSetKey, EncodedValue, Insn,
         ExceptionHandler extends org.jf.dexlib2.iface.ExceptionHandler> extends IndexSection<ClassKey> {
     @Nonnull Collection<? extends ClassKey> getSortedClasses();
 
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 9c979b74..3f297e6e 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java
@@ -40,6 +40,7 @@ import org.jf.dexlib2.base.BaseAnnotation;
 import org.jf.dexlib2.dexbacked.raw.*;
 import org.jf.dexlib2.iface.Annotation;
 import org.jf.dexlib2.iface.TryBlock;
+import org.jf.dexlib2.iface.debug.DebugItem;
 import org.jf.dexlib2.iface.debug.LineNumber;
 import org.jf.dexlib2.iface.instruction.Instruction;
 import org.jf.dexlib2.iface.instruction.formats.*;
@@ -75,7 +76,6 @@ public abstract class DexWriter<
         TypeListKey,
         FieldKey, MethodKey,
         EncodedValue, AnnotationElement,
-        DebugItem extends org.jf.dexlib2.iface.debug.DebugItem,
         Insn extends Instruction, ExceptionHandler extends org.jf.dexlib2.iface.ExceptionHandler> {
     public static final int NO_INDEX = -1;
     public static final int NO_OFFSET = 0;
@@ -116,7 +116,7 @@ public abstract class DexWriter<
     protected final FieldSection<StringKey, TypeKey, FieldRefKey, FieldKey> fieldSection;
     protected final MethodSection<StringKey, TypeKey, ProtoKey, MethodRefKey, MethodKey> methodSection;
     protected final ClassSection<StringKey, TypeKey, TypeListKey, ClassKey, FieldKey, MethodKey, AnnotationSetKey,
-            EncodedValue, DebugItem, Insn, ExceptionHandler> classSection;
+            EncodedValue, Insn, ExceptionHandler> classSection;
     
     protected final TypeListSection<TypeKey, TypeListKey> typeListSection;
     protected final AnnotationSection<StringKey, TypeKey, AnnotationKey, AnnotationElement, EncodedValue> annotationSection;
@@ -130,7 +130,7 @@ public abstract class DexWriter<
                         FieldSection<StringKey, TypeKey, FieldRefKey, FieldKey> fieldSection,
                         MethodSection<StringKey, TypeKey, ProtoKey, MethodRefKey, MethodKey> methodSection,
                         ClassSection<StringKey, TypeKey, TypeListKey, ClassKey, FieldKey, MethodKey, AnnotationSetKey,
-                                EncodedValue, DebugItem, Insn, ExceptionHandler> classSection,
+                                EncodedValue, Insn, ExceptionHandler> classSection,
                         TypeListSection<TypeKey, TypeListKey> typeListSection,
                         AnnotationSection<StringKey, TypeKey, AnnotationKey, AnnotationElement,
                                 EncodedValue> annotationSection,
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 cda9a4e2..215f1abc 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
@@ -37,15 +37,13 @@ import com.google.common.collect.*;
 import org.jf.dexlib2.DebugItemType;
 import org.jf.dexlib2.iface.Field;
 import org.jf.dexlib2.iface.TryBlock;
-import org.jf.dexlib2.iface.debug.EndLocal;
-import org.jf.dexlib2.iface.debug.LineNumber;
-import org.jf.dexlib2.iface.debug.RestartLocal;
+import org.jf.dexlib2.iface.debug.*;
+import org.jf.dexlib2.iface.reference.StringReference;
+import org.jf.dexlib2.iface.reference.TypeReference;
 import org.jf.dexlib2.iface.value.EncodedValue;
 import org.jf.dexlib2.util.EncodedValueUtils;
 import org.jf.dexlib2.writer.ClassSection;
 import org.jf.dexlib2.writer.DebugWriter;
-import org.jf.dexlib2.writer.builder.BuilderDebugItem.BuilderSetSourceFile;
-import org.jf.dexlib2.writer.builder.BuilderDebugItem.BuilderStartLocal;
 import org.jf.dexlib2.writer.builder.BuilderEncodedValues.BuilderEncodedValue;
 import org.jf.util.AbstractForwardSequentialList;
 import org.jf.util.CollectionUtils;
@@ -59,8 +57,8 @@ import java.util.Map.Entry;
 import java.util.concurrent.ConcurrentMap;
 
 public class BuilderClassPool implements ClassSection<BuilderStringReference, BuilderTypeReference, BuilderTypeList,
-        BuilderClassDef, BuilderField, BuilderMethod, BuilderAnnotationSet, BuilderEncodedValue, BuilderDebugItem,
-        BuilderInstruction, BuilderExceptionHandler> {
+        BuilderClassDef, BuilderField, BuilderMethod, BuilderAnnotationSet, BuilderEncodedValue, BuilderInstruction,
+        BuilderExceptionHandler> {
     @Nonnull private final ConcurrentMap<String, BuilderClassDef> internedItems =
             Maps.newConcurrentMap();
 
@@ -266,7 +264,7 @@ public class BuilderClassPool implements ClassSection<BuilderStringReference, Bu
     }
 
     @Nullable @Override
-    public Iterable<? extends BuilderDebugItem> getDebugItems(@Nonnull BuilderMethod builderMethod) {
+    public Iterable<? extends DebugItem> getDebugItems(@Nonnull BuilderMethod builderMethod) {
         BuilderMethodImplementation impl = builderMethod.getImplementation();
         if (impl == null) {
             return null;
@@ -353,17 +351,41 @@ public class BuilderClassPool implements ClassSection<BuilderStringReference, Bu
         return builderMethod.debugInfoOffset;
     }
 
+    @Nullable private BuilderStringReference checkStringReference(@Nullable StringReference stringReference) {
+        if (stringReference == null) {
+            return null;
+        }
+        try {
+            return (BuilderStringReference)stringReference;
+        } catch (ClassCastException ex) {
+            throw new IllegalStateException("Only StringReference instances returned by " +
+                    "DexBuilder.internStringReference or DexBuilder.internNullableStringReference may be used.");
+        }
+    }
+
+    @Nullable private BuilderTypeReference checkTypeReference(@Nullable TypeReference typeReference) {
+        if (typeReference == null) {
+            return null;
+        }
+        try {
+            return (BuilderTypeReference)typeReference;
+        } catch (ClassCastException ex) {
+            throw new IllegalStateException("Only TypeReference instances returned by " +
+                    "DexBuilder.internTypeReference or DexBuilder.internNullableTypeReference may be used.");
+        }
+    }
+
     @Override
     public void writeDebugItem(@Nonnull DebugWriter<BuilderStringReference, BuilderTypeReference> writer,
-                               BuilderDebugItem debugItem) throws IOException {
+                               DebugItem debugItem) throws IOException {
         switch (debugItem.getDebugItemType()) {
             case DebugItemType.START_LOCAL: {
-                BuilderStartLocal startLocal = (BuilderStartLocal)debugItem;
+                StartLocal startLocal = (StartLocal)debugItem;
                 writer.writeStartLocal(startLocal.getCodeAddress(),
-                        startLocal.register,
-                        startLocal.name,
-                        startLocal.type,
-                        startLocal.signature);
+                        startLocal.getRegister(),
+                        checkStringReference(startLocal.getNameReference()),
+                        checkTypeReference(startLocal.getTypeReference()),
+                        checkStringReference(startLocal.getSignatureReference()));
                 break;
             }
             case DebugItemType.END_LOCAL: {
@@ -390,8 +412,9 @@ public class BuilderClassPool implements ClassSection<BuilderStringReference, Bu
                 break;
             }
             case DebugItemType.SET_SOURCE_FILE: {
-                BuilderSetSourceFile setSourceFile = (BuilderSetSourceFile)debugItem;
-                writer.writeSetSourceFile(setSourceFile.getCodeAddress(), setSourceFile.sourceFile);
+                SetSourceFile setSourceFile = (SetSourceFile)debugItem;
+                writer.writeSetSourceFile(setSourceFile.getCodeAddress(),
+                        checkStringReference(setSourceFile.getSourceFileReference()));
             }
             default:
                 throw new ExceptionWithContext("Unexpected debug item type: %d", debugItem.getDebugItemType());
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderDebugItem.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderDebugItem.java
deleted file mode 100644
index 85a62f45..00000000
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderDebugItem.java
+++ /dev/null
@@ -1,168 +0,0 @@
-/*
- * Copyright 2013, 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.dexlib2.writer.builder;
-
-import org.jf.dexlib2.DebugItemType;
-import org.jf.dexlib2.iface.debug.*;
-import org.jf.dexlib2.immutable.debug.ImmutableEpilogueBegin;
-import org.jf.dexlib2.immutable.debug.ImmutableLineNumber;
-import org.jf.dexlib2.immutable.debug.ImmutablePrologueEnd;
-
-import javax.annotation.Nullable;
-
-public abstract interface BuilderDebugItem extends DebugItem {
-    abstract static class BaseBuilderDebugItem implements BuilderDebugItem {
-        final int codeAddress;
-
-        public BaseBuilderDebugItem(int codeAddress) {
-            this.codeAddress = codeAddress;
-        }
-
-        @Override public int getCodeAddress() { return codeAddress; }
-    }
-
-    public static class BuilderStartLocal extends BaseBuilderDebugItem implements StartLocal {
-        final int register;
-        @Nullable final BuilderStringReference name;
-        @Nullable final BuilderTypeReference type;
-        @Nullable final BuilderStringReference signature;
-
-        BuilderStartLocal(int codeAddress,
-                                 int register,
-                                 @Nullable BuilderStringReference name,
-                                 @Nullable BuilderTypeReference type,
-                                 @Nullable BuilderStringReference signature) {
-            super(codeAddress);
-            this.register = register;
-            this.name = name;
-            this.type = type;
-            this.signature = signature;
-        }
-
-        @Override public int getRegister() { return register; }
-        @Nullable @Override public String getName() { return name==null?null:name.getString(); }
-        @Nullable @Override public String getType() { return type==null?null:type.getType(); }
-        @Nullable @Override public String getSignature() { return signature==null?null:signature.getString(); }
-
-        @Override public int getDebugItemType() { return DebugItemType.START_LOCAL; }
-    }
-
-    public static class BuilderEndLocal extends BaseBuilderDebugItem implements EndLocal {
-        private final int register;
-
-        BuilderEndLocal(int codeAddress, int register) {
-            super(codeAddress);
-            this.register = register;
-        }
-
-        @Override public int getRegister() {
-            return register;
-        }
-
-        @Override public int getDebugItemType() {
-            return DebugItemType.END_LOCAL;
-        }
-
-        @Nullable @Override public String getName() {
-            return null;
-        }
-
-        @Nullable @Override public String getType() {
-            return null;
-        }
-
-        @Nullable @Override public String getSignature() {
-            return null;
-        }
-    }
-
-    public static class BuilderRestartLocal extends BaseBuilderDebugItem implements RestartLocal {
-        private final int register;
-
-        BuilderRestartLocal(int codeAddress, int register) {
-            super(codeAddress);
-            this.register = register;
-        }
-
-        @Override public int getRegister() {
-            return register;
-        }
-
-        @Override public int getDebugItemType() {
-            return DebugItemType.RESTART_LOCAL;
-        }
-
-        @Nullable @Override public String getName() {
-            return null;
-        }
-
-        @Nullable @Override public String getType() {
-            return null;
-        }
-
-        @Nullable @Override public String getSignature() {
-            return null;
-        }
-    }
-    
-    public static class BuilderPrologueEnd extends ImmutablePrologueEnd implements BuilderDebugItem {
-        BuilderPrologueEnd(int codeAddress) {
-            super(codeAddress);
-        }
-    }
-
-    public static class BuilderEpilogueBegin extends ImmutableEpilogueBegin implements BuilderDebugItem {
-        BuilderEpilogueBegin(int codeAddress) {
-            super(codeAddress);
-        }
-    }
-
-    public static class BuilderLineNumber extends ImmutableLineNumber implements BuilderDebugItem {
-        BuilderLineNumber(int codeAddress, int lineNumber) {
-            super(codeAddress, lineNumber);
-        }
-    }
-
-    public static class BuilderSetSourceFile extends BaseBuilderDebugItem implements SetSourceFile {
-        @Nullable final BuilderStringReference sourceFile;
-
-        BuilderSetSourceFile(int codeAddress,
-                                    @Nullable BuilderStringReference sourceFile) {
-            super(codeAddress);
-            this.sourceFile = sourceFile;
-        }
-
-        @Nullable @Override public String getSourceFile() { return sourceFile==null?null:sourceFile.getString(); }
-
-        @Override public int getDebugItemType() { return DebugItemType.SET_SOURCE_FILE; }
-    }
-}
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderMethodImplementation.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderMethodImplementation.java
index 5c901c02..b0c7073f 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderMethodImplementation.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/builder/BuilderMethodImplementation.java
@@ -32,6 +32,7 @@
 package org.jf.dexlib2.writer.builder;
 
 import org.jf.dexlib2.iface.MethodImplementation;
+import org.jf.dexlib2.iface.debug.DebugItem;
 
 import javax.annotation.Nonnull;
 import java.util.List;
@@ -40,12 +41,12 @@ public class BuilderMethodImplementation implements MethodImplementation {
     protected final int registerCount;
     @Nonnull protected final List<? extends BuilderInstruction> instructions;
     @Nonnull protected final List<? extends BuilderTryBlock> tryBlocks;
-    @Nonnull protected final List<? extends BuilderDebugItem> debugItems;
+    @Nonnull protected final List<? extends DebugItem> debugItems;
 
     public BuilderMethodImplementation(int registerCount,
                                        @Nonnull List<? extends BuilderInstruction> instructions,
                                        @Nonnull List<? extends BuilderTryBlock> tryBlocks,
-                                       @Nonnull List<? extends BuilderDebugItem> debugItems) {
+                                       @Nonnull List<? extends DebugItem> debugItems) {
         this.registerCount = registerCount;
         this.instructions = instructions;
         this.tryBlocks = tryBlocks;
@@ -55,5 +56,5 @@ public class BuilderMethodImplementation implements MethodImplementation {
     @Override public int getRegisterCount() { return registerCount; }
     @Nonnull @Override public List<? extends BuilderInstruction> getInstructions() { return instructions; }
     @Nonnull @Override public List<? extends BuilderTryBlock> getTryBlocks() { return tryBlocks; }
-    @Nonnull @Override public List<? extends BuilderDebugItem> getDebugItems() { return debugItems; }
+    @Nonnull @Override public List<? extends DebugItem> getDebugItems() { return debugItems; }
 }
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 3d4f3025..e3c6cd13 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
@@ -38,10 +38,10 @@ import com.google.common.collect.Lists;
 import org.jf.dexlib2.ValueType;
 import org.jf.dexlib2.iface.Annotation;
 import org.jf.dexlib2.iface.MethodParameter;
+import org.jf.dexlib2.iface.debug.DebugItem;
 import org.jf.dexlib2.iface.reference.*;
 import org.jf.dexlib2.iface.value.*;
 import org.jf.dexlib2.writer.DexWriter;
-import org.jf.dexlib2.writer.builder.BuilderDebugItem.*;
 import org.jf.dexlib2.writer.builder.BuilderEncodedValues.*;
 import org.jf.util.ExceptionWithContext;
 
@@ -56,7 +56,7 @@ import java.util.Set;
 public class DexBuilder extends DexWriter<BuilderStringReference, BuilderStringReference, BuilderTypeReference,
         BuilderTypeReference, BuilderProtoReference, BuilderFieldReference, BuilderMethodReference, BuilderReference,
         BuilderClassDef, BuilderAnnotation, BuilderAnnotationSet, BuilderTypeList, BuilderField, BuilderMethod,
-        BuilderEncodedValue, BuilderAnnotationElement, BuilderDebugItem, BuilderInstruction, BuilderExceptionHandler> {
+        BuilderEncodedValue, BuilderAnnotationElement, BuilderInstruction, BuilderExceptionHandler> {
 
     private final BuilderContext context;
 
@@ -110,7 +110,7 @@ public class DexBuilder extends DexWriter<BuilderStringReference, BuilderStringR
             int registerCount,
             @Nullable List<? extends BuilderInstruction> instructions,
             @Nullable List<? extends BuilderTryBlock> tryBlocks,
-            @Nullable List<? extends BuilderDebugItem> debugItems) {
+            @Nullable List<? extends DebugItem> debugItems) {
         if (instructions == null) {
             instructions = ImmutableList.of();
         }
@@ -232,40 +232,6 @@ public class DexBuilder extends DexWriter<BuilderStringReference, BuilderStringR
                 handlerCodeAddress);
     }
 
-    @Nonnull public BuilderStartLocal internStartLocal(int codeAddress, int register, @Nullable String name,
-                                                        @Nullable String type, @Nullable String signature) {
-        return new BuilderStartLocal(codeAddress,
-                register,
-                context.stringPool.internNullableString(name),
-                context.typePool.internNullableType(type),
-                context.stringPool.internNullableString(signature));
-    }
-
-    @Nonnull public BuilderSetSourceFile internSetSourceFile(int codeAddress, @Nullable String sourceFile) {
-        return new BuilderSetSourceFile(codeAddress,
-                context.stringPool.internNullableString(sourceFile));
-    }
-
-    @Nonnull public BuilderEndLocal internEndLocal(int codeAddress, int register) {
-        return new BuilderEndLocal(codeAddress, register);
-    }
-
-    @Nonnull public BuilderRestartLocal internRestartLocal(int codeAddress, int register) {
-        return new BuilderRestartLocal(codeAddress, register);
-    }
-
-    @Nonnull public BuilderPrologueEnd internPrologueEnd(int codeAddress) {
-        return new BuilderPrologueEnd(codeAddress);
-    }
-
-    @Nonnull public BuilderEpilogueBegin internEpilogueBegin(int codeAddress) {
-        return new BuilderEpilogueBegin(codeAddress);
-    }
-
-    @Nonnull public BuilderLineNumber internLineNumber(int codeAddress, int lineNumber) {
-        return new BuilderLineNumber(codeAddress, lineNumber);
-    }
-
     @Override protected void writeEncodedValue(@Nonnull InternalEncodedValueWriter writer,
                                                @Nonnull BuilderEncodedValue encodedValue) throws IOException {
         switch (encodedValue.getValueType()) {
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 cb316082..8ff826de 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
@@ -60,7 +60,7 @@ import java.util.Map.Entry;
 public class ClassPool implements ClassSection<CharSequence, CharSequence,
         TypeListPool.Key<? extends Collection<? extends CharSequence>>, PoolClassDef, Field, PoolMethod,
         Set<? extends Annotation>,
-        EncodedValue, DebugItem, Instruction, ExceptionHandler> {
+        EncodedValue, Instruction, ExceptionHandler> {
     @Nonnull private HashMap<String, PoolClassDef> internedItems = Maps.newHashMap();
 
     @Nonnull private final StringPool stringPool;
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/DexPool.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/DexPool.java
index 1eda265a..887a30da 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/DexPool.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/pool/DexPool.java
@@ -33,7 +33,6 @@ package org.jf.dexlib2.writer.pool;
 
 import org.jf.dexlib2.ValueType;
 import org.jf.dexlib2.iface.*;
-import org.jf.dexlib2.iface.debug.DebugItem;
 import org.jf.dexlib2.iface.instruction.Instruction;
 import org.jf.dexlib2.iface.reference.*;
 import org.jf.dexlib2.iface.value.*;
@@ -51,7 +50,7 @@ public class DexPool extends DexWriter<CharSequence, StringReference, CharSequen
         FieldReference, MethodReference, Reference, PoolClassDef,
         Annotation, Set<? extends Annotation>,
         TypeListPool.Key<? extends Collection<? extends CharSequence>>, Field, PoolMethod,
-        EncodedValue, AnnotationElement, DebugItem, Instruction, ExceptionHandler> {
+        EncodedValue, AnnotationElement, Instruction, ExceptionHandler> {
 
     public static DexPool makeDexPool() {
         return makeDexPool(15);