diff --git a/benchmark/src/main/java/org/capnproto/benchmark/TestCase.java b/benchmark/src/main/java/org/capnproto/benchmark/TestCase.java
index 6ef36ad..e74f336 100644
--- a/benchmark/src/main/java/org/capnproto/benchmark/TestCase.java
+++ b/benchmark/src/main/java/org/capnproto/benchmark/TestCase.java
@@ -7,8 +7,6 @@ import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.FileDescriptor;
 
-import org.capnproto.FromStructReader;
-import org.capnproto.FromStructBuilder;
 import org.capnproto.StructFactory;
 import org.capnproto.MessageBuilder;
 import org.capnproto.MessageReader;
diff --git a/compiler/src/main/cpp/capnpc-java.c++ b/compiler/src/main/cpp/capnpc-java.c++
index f20b183..b900380 100644
--- a/compiler/src/main/cpp/capnpc-java.c++
+++ b/compiler/src/main/cpp/capnpc-java.c++
@@ -1189,11 +1189,11 @@ private:
 
         spaces(indent), "  public static class Factory implements org.capnproto.StructFactory<Builder, Reader> {\n",
         spaces(indent),
-        "    public final Reader fromStructReader(org.capnproto.SegmentReader segment, int data,",
+        "    public final Reader constructReader(org.capnproto.SegmentReader segment, int data,",
         "int pointers, int dataSize, short pointerCount, byte bit0Offset, int nestingLimit) {\n",
         spaces(indent), "      return new Reader(segment,data,pointers,dataSize,pointerCount,bit0Offset,nestingLimit);\n",
         spaces(indent), "    }\n",
-        spaces(indent), "    public final Builder fromStructBuilder(org.capnproto.SegmentBuilder segment, int data,",
+        spaces(indent), "    public final Builder constructBuilder(org.capnproto.SegmentBuilder segment, int data,",
         "int pointers, int dataSize, short pointerCount, byte bit0Offset) {\n",
         spaces(indent), "      return new Builder(segment, data, pointers, dataSize, pointerCount, bit0Offset);\n",
         spaces(indent), "    }\n",
diff --git a/runtime/src/main/java/org/capnproto/AnyPointer.java b/runtime/src/main/java/org/capnproto/AnyPointer.java
index d465bf0..a4e38aa 100644
--- a/runtime/src/main/java/org/capnproto/AnyPointer.java
+++ b/runtime/src/main/java/org/capnproto/AnyPointer.java
@@ -9,7 +9,7 @@ public final class AnyPointer {
             this.reader = reader;
         }
 
-        public final <T> T getAsStruct(FromStructReader<T> factory) {
+        public final <T> T getAsStruct(StructReader.Factory<T> factory) {
             return this.reader.getStruct(factory);
         }
 
@@ -25,7 +25,7 @@ public final class AnyPointer {
             this.builder = builder;
         }
 
-        public final <T> T initAsStruct(FromStructBuilder<T> factory) {
+        public final <T> T initAsStruct(StructBuilder.Factory<T> factory) {
             return this.builder.initStruct(factory);
         }
 
diff --git a/runtime/src/main/java/org/capnproto/FromStructBuilder.java b/runtime/src/main/java/org/capnproto/FromStructBuilder.java
deleted file mode 100644
index 30ee6f6..0000000
--- a/runtime/src/main/java/org/capnproto/FromStructBuilder.java
+++ /dev/null
@@ -1,7 +0,0 @@
-package org.capnproto;
-
-public interface FromStructBuilder<T> {
-    T fromStructBuilder(SegmentBuilder segment, int data, int pointers, int dataSize,
-                        short pointerCount, byte bit0Offset);
-    StructSize structSize();
-}
diff --git a/runtime/src/main/java/org/capnproto/FromStructReader.java b/runtime/src/main/java/org/capnproto/FromStructReader.java
deleted file mode 100644
index 0556d7e..0000000
--- a/runtime/src/main/java/org/capnproto/FromStructReader.java
+++ /dev/null
@@ -1,7 +0,0 @@
-package org.capnproto;
-
-public interface FromStructReader<T> {
-    T fromStructReader(SegmentReader segment, int data, int pointers,
-                       int dataSize, short pointerCount,
-                       byte bit0Offset, int nestingLimit);
-}
diff --git a/runtime/src/main/java/org/capnproto/ListBuilder.java b/runtime/src/main/java/org/capnproto/ListBuilder.java
index 582130b..205938a 100644
--- a/runtime/src/main/java/org/capnproto/ListBuilder.java
+++ b/runtime/src/main/java/org/capnproto/ListBuilder.java
@@ -85,17 +85,17 @@ public class ListBuilder {
         this.segment.buffer.putDouble(this.ptr + index * 8, value);
     }
 
-    protected final <T> T _getStructElement(FromStructBuilder<T> factory, int index) {
+    protected final <T> T _getStructElement(StructBuilder.Factory<T> factory, int index) {
         int indexBit = index * this.step;
         int structData = this.ptr + indexBit / 8 ;
         int structPointers = (structData + (this.structDataSize / 8)) / 8;
 
-        return factory.fromStructBuilder(this.segment,
-                                         structData,
-                                         structPointers,
-                                         this.structDataSize,
-                                         this.structPointerCount,
-                                         (byte)(indexBit % 8));
+        return factory.constructBuilder(this.segment,
+                                        structData,
+                                        structPointers,
+                                        this.structDataSize,
+                                        this.structPointerCount,
+                                        (byte)(indexBit % 8));
     }
 
 
diff --git a/runtime/src/main/java/org/capnproto/ListReader.java b/runtime/src/main/java/org/capnproto/ListReader.java
index 58be227..cebb68c 100644
--- a/runtime/src/main/java/org/capnproto/ListReader.java
+++ b/runtime/src/main/java/org/capnproto/ListReader.java
@@ -66,7 +66,7 @@ public class ListReader {
         return this.segment.buffer.getDouble(this.ptr + index * 8);
     }
 
-    protected <T> T _getStructElement(FromStructReader<T> factory, int index) {
+    protected <T> T _getStructElement(StructReader.Factory<T> factory, int index) {
         // TODO check nesting limit
 
         int indexBit = index * this.step;
@@ -74,8 +74,8 @@ public class ListReader {
         int structData = this.ptr + (indexBit / 8);
         int structPointers = structData + (this.structDataSize / 8);
 
-        return factory.fromStructReader(this.segment, structData, structPointers / 8, this.structDataSize,
-                                        this.structPointerCount, (byte) (indexBit % 8), this.nestingLimit - 1);
+        return factory.constructReader(this.segment, structData, structPointers / 8, this.structDataSize,
+                                       this.structPointerCount, (byte) (indexBit % 8), this.nestingLimit - 1);
     }
 
     protected PointerReader _getPointerElement(int index) {
diff --git a/runtime/src/main/java/org/capnproto/MessageBuilder.java b/runtime/src/main/java/org/capnproto/MessageBuilder.java
index 4f4f3bd..a4d0eb8 100644
--- a/runtime/src/main/java/org/capnproto/MessageBuilder.java
+++ b/runtime/src/main/java/org/capnproto/MessageBuilder.java
@@ -19,11 +19,11 @@ public final class MessageBuilder {
                                       allocationStrategy);
     }
 
-    public <T> T getRoot(FromStructBuilder<T> factory) {
+    public <T> T getRoot(StructBuilder.Factory<T> factory) {
         throw new Error("unimplemented");
     }
 
-    public <T> T initRoot(FromStructBuilder<T> factory) {
+    public <T> T initRoot(StructBuilder.Factory <T> factory) {
         SegmentBuilder rootSegment = this.arena.segments.get(0);
         int location = rootSegment.allocate(1);
         if (location == SegmentBuilder.FAILED_ALLOCATION) {
diff --git a/runtime/src/main/java/org/capnproto/MessageReader.java b/runtime/src/main/java/org/capnproto/MessageReader.java
index fa2e564..0ade469 100644
--- a/runtime/src/main/java/org/capnproto/MessageReader.java
+++ b/runtime/src/main/java/org/capnproto/MessageReader.java
@@ -9,7 +9,7 @@ public final class MessageReader {
         this.arena = new ReaderArena(segmentSlices);
     }
 
-    public <T> T getRoot(FromStructReader<T> factory) {
+    public <T> T getRoot(StructReader.Factory<T> factory) {
         SegmentReader segment = this.arena.tryGetSegment(0);
         PointerReader pointerReader = PointerReader.getRoot(segment, 0,
                                                             0x7fffffff /* XXX */);
diff --git a/runtime/src/main/java/org/capnproto/PointerBuilder.java b/runtime/src/main/java/org/capnproto/PointerBuilder.java
index 68dd117..1cc2c83 100644
--- a/runtime/src/main/java/org/capnproto/PointerBuilder.java
+++ b/runtime/src/main/java/org/capnproto/PointerBuilder.java
@@ -18,11 +18,11 @@ public final class PointerBuilder {
     }
 
 
-    public final <T> T getStruct(FromStructBuilder<T> factory) {
+    public final <T> T getStruct(StructBuilder.Factory<T> factory) {
         return WireHelpers.getWritableStructPointer(factory, this.pointer, this.segment, factory.structSize(), null, 0);
     }
 
-    public final <T> T getStruct(FromStructBuilder<T> factory, SegmentReader defaultReader, int defaultOffset) {
+    public final <T> T getStruct(StructBuilder.Factory<T> factory, SegmentReader defaultReader, int defaultOffset) {
         return WireHelpers.getWritableStructPointer(factory, this.pointer, this.segment, factory.structSize(),
                                                     defaultReader, defaultOffset);
     }
@@ -54,7 +54,7 @@ public final class PointerBuilder {
                                                   defaultSize);
     }
 
-    public final <T> T initStruct(FromStructBuilder<T> factory) {
+    public final <T> T initStruct(StructBuilder.Factory<T> factory) {
         return WireHelpers.initStructPointer(factory, this.pointer, this.segment, factory.structSize());
     }
 
diff --git a/runtime/src/main/java/org/capnproto/PointerReader.java b/runtime/src/main/java/org/capnproto/PointerReader.java
index d0b3d2e..1e1d1f7 100644
--- a/runtime/src/main/java/org/capnproto/PointerReader.java
+++ b/runtime/src/main/java/org/capnproto/PointerReader.java
@@ -28,7 +28,7 @@ public final class PointerReader {
         return this.segment.buffer.getLong(this.pointer) == 0;
     }
 
-    public <T> T getStruct(FromStructReader<T> factory) {
+    public <T> T getStruct(StructReader.Factory<T> factory) {
         return WireHelpers.readStructPointer(factory,
                                              this.segment,
                                              this.pointer,
@@ -36,7 +36,7 @@ public final class PointerReader {
                                              this.nestingLimit);
     }
 
-    public <T> T getStruct(FromStructReader<T> factory, SegmentReader defaultSegment, int defaultOffset) {
+    public <T> T getStruct(StructReader.Factory<T> factory, SegmentReader defaultSegment, int defaultOffset) {
         return WireHelpers.readStructPointer(factory,
                                              this.segment,
                                              this.pointer,
diff --git a/runtime/src/main/java/org/capnproto/StructBuilder.java b/runtime/src/main/java/org/capnproto/StructBuilder.java
index 2e7932a..8b24772 100644
--- a/runtime/src/main/java/org/capnproto/StructBuilder.java
+++ b/runtime/src/main/java/org/capnproto/StructBuilder.java
@@ -1,6 +1,13 @@
 package org.capnproto;
 
 public class StructBuilder {
+
+    public interface Factory<T> {
+        T constructBuilder(SegmentBuilder segment, int data, int pointers, int dataSize,
+                           short pointerCount, byte bit0Offset);
+        StructSize structSize();
+    }
+
     protected final SegmentBuilder segment;
     protected final int data; // byte offset to data section
     protected final int pointers; // word offset of pointer section
diff --git a/runtime/src/main/java/org/capnproto/StructFactory.java b/runtime/src/main/java/org/capnproto/StructFactory.java
index 9fa9742..ba2d760 100644
--- a/runtime/src/main/java/org/capnproto/StructFactory.java
+++ b/runtime/src/main/java/org/capnproto/StructFactory.java
@@ -1,7 +1,5 @@
 package org.capnproto;
 
-public interface StructFactory<Builder, Reader> extends FromStructBuilder<Builder>, FromStructReader<Reader>{
-
+public interface StructFactory<Builder, Reader> extends StructBuilder.Factory<Builder>, StructReader.Factory<Reader>{
     public Reader asReader(Builder builder);
-
 }
diff --git a/runtime/src/main/java/org/capnproto/StructList.java b/runtime/src/main/java/org/capnproto/StructList.java
index 99ed666..7a3adaa 100644
--- a/runtime/src/main/java/org/capnproto/StructList.java
+++ b/runtime/src/main/java/org/capnproto/StructList.java
@@ -54,9 +54,9 @@ public final class StructList {
     }
 
     public static final class Reader<T> extends ListReader implements Iterable<T> {
-        public final FromStructReader<T> factory;
+        public final StructReader.Factory<T> factory;
 
-        public Reader(FromStructReader<T> factory,
+        public Reader(StructReader.Factory<T> factory,
                       SegmentReader segment,
                       int ptr,
                       int elementCount, int step,
@@ -95,9 +95,9 @@ public final class StructList {
     }
 
     public static final class Builder<T> extends ListBuilder implements Iterable<T> {
-        public final FromStructBuilder<T> factory;
+        public final StructBuilder.Factory<T> factory;
 
-        public Builder(FromStructBuilder<T> factory,
+        public Builder(StructBuilder.Factory<T> factory,
                        SegmentBuilder segment, int ptr,
                        int elementCount, int step,
                        int structDataSize, short structPointerCount){
diff --git a/runtime/src/main/java/org/capnproto/StructReader.java b/runtime/src/main/java/org/capnproto/StructReader.java
index e7f2f1b..b5f02e3 100644
--- a/runtime/src/main/java/org/capnproto/StructReader.java
+++ b/runtime/src/main/java/org/capnproto/StructReader.java
@@ -2,6 +2,13 @@ package org.capnproto;
 
 
 public class StructReader {
+
+    public interface Factory<T> {
+        T constructReader(SegmentReader segment, int data, int pointers,
+                          int dataSize, short pointerCount,
+                          byte bit0Offset, int nestingLimit);
+    }
+
     protected final SegmentReader segment;
     protected final int data; //byte offset to data section
     protected final int pointers; // word offset of pointer section
diff --git a/runtime/src/main/java/org/capnproto/WireHelpers.java b/runtime/src/main/java/org/capnproto/WireHelpers.java
index b015e61..b739c75 100644
--- a/runtime/src/main/java/org/capnproto/WireHelpers.java
+++ b/runtime/src/main/java/org/capnproto/WireHelpers.java
@@ -146,18 +146,18 @@ final class WireHelpers {
     }
 
 
-    static <T> T initStructPointer(FromStructBuilder<T> factory,
+    static <T> T initStructPointer(StructBuilder.Factory<T> factory,
                                    int refOffset,
                                    SegmentBuilder segment,
                                    StructSize size) {
         AllocateResult allocation = allocate(refOffset, segment, size.total(), WirePointer.STRUCT);
         StructPointer.setFromStructSize(allocation.segment.buffer, allocation.refOffset, size);
-        return factory.fromStructBuilder(allocation.segment, allocation.ptr * Constants.BYTES_PER_WORD,
+        return factory.constructBuilder(allocation.segment, allocation.ptr * Constants.BYTES_PER_WORD,
                                          allocation.ptr + size.data,
                                          size.data * 64, size.pointers, (byte)0);
     }
 
-    static <T> T getWritableStructPointer(FromStructBuilder<T> factory,
+    static <T> T getWritableStructPointer(StructBuilder.Factory<T> factory,
                                           int refOffset,
                                           SegmentBuilder segment,
                                           StructSize size,
@@ -181,9 +181,9 @@ final class WireHelpers {
         if (oldDataSize < size.data || oldPointerCount < size.pointers) {
             throw new Error("unimplemented");
         } else {
-            return factory.fromStructBuilder(resolved.segment, resolved.ptr * Constants.BYTES_PER_WORD,
-                                             oldPointerSectionOffset, oldDataSize * Constants.BITS_PER_WORD,
-                                             oldPointerCount, (byte)0);
+            return factory.constructBuilder(resolved.segment, resolved.ptr * Constants.BYTES_PER_WORD,
+                                            oldPointerSectionOffset, oldDataSize * Constants.BITS_PER_WORD,
+                                            oldPointerCount, (byte)0);
         }
 
     }
@@ -435,7 +435,7 @@ final class WireHelpers {
 
     }
 
-    static <T> T readStructPointer(FromStructReader<T> factory,
+    static <T> T readStructPointer(StructReader.Factory<T> factory,
                                    SegmentReader segment,
                                    int refOffset,
                                    SegmentReader defaultSegment,
@@ -444,7 +444,7 @@ final class WireHelpers {
         long ref = WirePointer.get(segment.buffer, refOffset);
         if (WirePointer.isNull(ref)) {
             if (defaultSegment == null) {
-                return factory.fromStructReader(SegmentReader.EMPTY, 0, 0, 0, (short) 0, (byte) 0, 0x7fffffff);
+                return factory.constructReader(SegmentReader.EMPTY, 0, 0, 0, (short) 0, (byte) 0, 0x7fffffff);
             } else {
                 segment = defaultSegment;
                 refOffset = defaultOffset;
@@ -468,7 +468,7 @@ final class WireHelpers {
 
         // TODO "bounds_check" (read limiting)
 
-        return factory.fromStructReader(resolved.segment,
+        return factory.constructReader(resolved.segment,
                                         resolved.ptr * Constants.BYTES_PER_WORD,
                                         (resolved.ptr + dataSizeWords),
                                         dataSizeWords * Constants.BITS_PER_WORD,
diff --git a/runtime/src/test/scala/org/capnproto/LayoutTest.scala b/runtime/src/test/scala/org/capnproto/LayoutTest.scala
index 76d37fb..2fffe16 100644
--- a/runtime/src/test/scala/org/capnproto/LayoutTest.scala
+++ b/runtime/src/test/scala/org/capnproto/LayoutTest.scala
@@ -5,9 +5,9 @@ import org.scalatest.FunSuite
 
 class LayoutSuite extends FunSuite {
 
-  class BareStructReader extends FromStructReader[StructReader] {
-    def fromStructReader(segment: org.capnproto.SegmentReader, data: Int, pointers: Int,
-                         dataSize: Int, pointerCount: Short, bit0Offset: Byte, nestingLimit:Int) : StructReader = {
+  class BareStructReader extends StructReader.Factory[StructReader] {
+    def constructReader(segment: org.capnproto.SegmentReader, data: Int, pointers: Int,
+                        dataSize: Int, pointerCount: Short, bit0Offset: Byte, nestingLimit:Int) : StructReader = {
       return new StructReader(segment,data,pointers,dataSize,pointerCount,bit0Offset,nestingLimit);
     }
   }
@@ -97,9 +97,9 @@ class LayoutSuite extends FunSuite {
   }
 
 
-  class BareStructBuilder(structSize : StructSize) extends FromStructBuilder[StructBuilder] {
+  class BareStructBuilder(structSize : StructSize) extends StructBuilder.Factory[StructBuilder] {
 
-    def fromStructBuilder(segment: org.capnproto.SegmentBuilder, data: Int, pointers: Int,
+    def constructBuilder(segment: org.capnproto.SegmentBuilder, data: Int, pointers: Int,
                           dataSize: Int, pointerCount: Short, bit0Offset: Byte) : StructBuilder = {
       return new StructBuilder(segment,data,pointers,dataSize,pointerCount,bit0Offset);
     }