add some builder classes

Makefile

@@ -6,12 +6,16 @@ CAPNP_SOURCES=\
 	src/capnp/FromStructReader.java\
 	src/capnp/InputStreamMessageReader.java\
 	src/capnp/ListPointer.java\
+	src/capnp/ListBuilder.java\
 	src/capnp/ListReader.java\
 	src/capnp/MessageReader.java\
+	src/capnp/PointerBuilder.java\
 	src/capnp/PointerReader.java\
+	src/capnp/SegmentBuilder.java\
 	src/capnp/SegmentReader.java\
-	src/capnp/StructReader.java\
+	src/capnp/StructBuilder.java\
 	src/capnp/StructPointer.java\
+	src/capnp/StructReader.java\
 	src/capnp/StructList.java\
 	src/capnp/Text.java\
 	src/capnp/WireHelpers.java\

src/capnp/ListBuilder.java

@@ -0,0 +1,24 @@
+package org.capnproto;
+
+public final class ListBuilder {
+    SegmentBuilder segment;
+    int ptr; // byte offset to front of list
+    int elementCount;
+    int step; // in bits
+    int structDataSize; // in bits
+    short structPointerCount;
+
+    public ListBuilder(SegmentBuilder segment, int ptr,
+                       int elementCount, int step,
+                       int structDataSize, short structPointerCount) {
+        this.segment = segment;
+        this.ptr = ptr;
+        this.elementCount = elementCount;
+        this.step = step;
+        this.structDataSize = structDataSize;
+        this.structPointerCount = structPointerCount;
+    }
+
+
+
+}

src/capnp/PointerBuilder.java

@@ -0,0 +1,11 @@
+package org.capnproto;
+
+public final class PointerBuilder {
+    public SegmentBuilder segment;
+    public int pointer; // word offset
+
+    public PointerBuilder(SegmentBuilder segment, int pointer) {
+        this.segment = segment;
+        this.pointer = pointer;
+    }
+}

src/capnp/SegmentBuilder.java

@@ -0,0 +1,9 @@
+package org.capnproto;
+
+import java.nio.ByteBuffer;
+
+public class SegmentBuilder extends SegmentReader {
+    public SegmentBuilder(ByteBuffer buf) {
+        super(buf);
+    }
+}

src/capnp/StructBuilder.java

@@ -0,0 +1,31 @@
+package org.capnproto;
+
+public final class StructBuilder {
+    public SegmentBuilder segment;
+    public int data; //byte offset to data section
+    public int pointers; // word offset of pointer section
+    public int dataSize; // in bits
+    public short pointerCount;
+    public byte bit0Offset;
+
+    public StructBuilder(SegmentBuilder segment, int data,
+                        int pointers, int dataSize, short pointerCount,
+                        byte bit0Offset) {
+        this.segment = segment;
+        this.data = data;
+        this.pointers = pointers;
+        this.dataSize = dataSize;
+        this.pointerCount = pointerCount;
+        this.bit0Offset = bit0Offset;
+    }
+
+
+    public int getIntField(int offset) {
+        return this.segment.ptr.getInt(this.data + offset * 4);
+    }
+
+    public void setIntField(int offset, int value) {
+        this.segment.ptr.putInt(this.data + offset * 4, value);
+    }
+
+}

src/capnp/StructReader.java

@@ -3,7 +3,6 @@ package org.capnproto;
 public class StructReader {
     public SegmentReader segment;
     public int data; //byte offset to data section
-
     public int pointers; // word offset of pointer section
     public int dataSize; // in bits
     public short pointerCount;