capnproto-java-rpc/runtime/src/main/java/org/capnproto/MessageBuilder.java

package org.capnproto;

public final class MessageBuilder {

    private final BuilderArena arena;

    public MessageBuilder() {
        this.arena = new BuilderArena(BuilderArena.SUGGESTED_FIRST_SEGMENT_WORDS,
                                      BuilderArena.SUGGESTED_ALLOCATION_STRATEGY);
    }

    public MessageBuilder(int firstSegmentWords) {
        this.arena = new BuilderArena(firstSegmentWords,
                                      BuilderArena.SUGGESTED_ALLOCATION_STRATEGY);
    }

    public MessageBuilder(int firstSegmentWords, BuilderArena.AllocationStrategy allocationStrategy) {
        this.arena = new BuilderArena(firstSegmentWords,
                                      allocationStrategy);
    }

    public <T> T getRoot(StructBuilder.Factory<T> factory) {
        throw new Error("unimplemented");
    }

    public <T> T initRoot(InitFromPointerBuilder<T> factory) {
        SegmentBuilder rootSegment = this.arena.segments.get(0);
        int location = rootSegment.allocate(1);
        if (location == SegmentBuilder.FAILED_ALLOCATION) {
            throw new Error("could not allocate root pointer");
        }

        AnyPointer.Builder ptr = new AnyPointer.Builder(rootSegment, location);
        return ptr.initAs(factory);
    }

    public final java.nio.ByteBuffer[] getSegmentsForOutput() {
        return this.arena.getSegmentsForOutput();
    }
}