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

// Copyright (c) 2013-2014 Sandstorm Development Group, Inc. and contributors
// Licensed under the MIT License:
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

package org.capnproto;

import java.nio.ByteBuffer;

public final class MessageReader {
    final ReaderArena arena;
    final int nestingLimit;

    public MessageReader(ByteBuffer[] segmentSlices, ReaderOptions options) {
        this.nestingLimit = options.nestingLimit;
        this.arena = new ReaderArena(segmentSlices, options.traversalLimitInWords);
    }

    public <T> T getRoot(FromPointerReader<T> factory) {
        SegmentReader segment = this.arena.tryGetSegment(0);
        AnyPointer.Reader any = new AnyPointer.Reader(segment, 0, this.nestingLimit);
        return any.getAs(factory);
    }
}