erjang.EBinary.java Source code

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Here is the source code for erjang.EBinary.java

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/**
 * This file is part of Erjang - A JVM-based Erlang VM
 *
 * Copyright (c) 2009 by Trifork
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *  
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 **/

package erjang;

import java.io.IOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.util.zip.CRC32;

import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;

public class EBinary extends EBitString {

    public static final EBinary EMPTY = new EBinary(new byte[0]);

    public EBinary(byte[] data, int byteOff, int byteLength) {
        super(data, byteOff, byteLength, 0);
    }

    /**
     * @param binaryValue
     */
    public EBinary(byte[] bytes) {
        this(bytes, 0, bytes.length);
    }

    private static final Type EBINARY_TYPE = Type.getType(EBinary.class);
    private static final String EBINARY_NAME = EBINARY_TYPE.getInternalName();

    @Override
    public Type emit_const(MethodVisitor fa) {
        char[] chs = new char[byteSize()];
        for (int i = 0; i < byteSize(); i++) {
            chs[i] = (char) (0xff & octetAt(i));
        }
        String str = new String(chs);

        fa.visitLdcInsn(str);
        fa.visitMethodInsn(Opcodes.INVOKESTATIC, EBINARY_NAME, "fromString",
                "(Ljava/lang/String;)L" + EBINARY_NAME + ";");

        return EBINARY_TYPE;
    }

    public static EBinary fromString(String str) {
        int size = str.length();
        byte[] data = new byte[size];
        for (int i = 0; i < str.length(); i++) {
            data[i] = (byte) str.charAt(i);
        }
        return new EBinary(data, 0, size);
    }

    public EBinary testBinary() {
        return this;
    }

    /**
     * @return
     */
    public byte[] getByteArray() {
        int octets = byteSize();
        byte[] res = new byte[octets];
        System.arraycopy(data, byteOffset(), res, 0, octets);
        return res;
    }

    public long crc() {
        CRC32 crc = new CRC32();

        int octets = byteSize();
        crc.update(data, byteOffset(), octets);
        return crc.getValue();
    }

    /**
     * @param barr
     * @throws IOException
     */
    public void appendTo(OutputStream barr) {
        try {
            barr.write(data, byteOffset(), byteSize());
        } catch (IOException e) {
            throw new Error(e);
        }
    }

    /**
     * @param barr
     * @throws IOException 
     * @throws IOException
     */
    public void writeTo(OutputStream o) throws IOException {
        o.write(data, byteOffset(), byteSize());
    }

    /**
     * @param data
     * @return
     */
    public static EBinary make(ByteBuffer data) {
        if (data == null || data.remaining() == 0)
            return EMPTY;
        return new EBinary(data.array(), data.arrayOffset() + data.position(), data.remaining());
    }

    /**
     * @return
     */
    public ByteBuffer toByteBuffer() {
        return ByteBuffer.wrap(this.data, byteOffset(), byteSize());
    }

    /**
     * @param eInputStream
     * @return
     */
    public static EBinary read(EInputStream eInputStream) throws IOException {
        byte[] data = eInputStream.read_binary();
        return new EBinary(data); //TODO: use a make().
    }

    /**
     * @return
     */
    public EInputStream getInputStream() {
        int octets = byteSize();
        return new EInputStream(data, byteOffset(), octets, EInputStream.DECODE_INT_LISTS_AS_STRINGS);
    }

    /**
     * @return true if this binary is all 7-bit bytes
     */
    public boolean is_7bit() {
        for (int i = 0; i < byteSize(); i++) {
            byte b = data[byteOffset() + i];
            if ((b & 0x80) != 0)
                return false;
        }
        return true;
    }

    @Override
    public void encode(EOutputStream eos) {
        eos.write_binary(getByteArray());
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder("<<\"");
        for (int i = 0; i < byteSize(); i++) {
            char b = (char) (0xff & byteAt(i * 8));
            if (b >= 32 && b < 127)
                EString.appendChar(sb, b);
            else
                return super.toString();
        }

        sb.append("\">>");
        return sb.toString();
    }

    public static EBinary make(byte[] res) {
        return new EBinary(res);
    }

    public EBinary sub_binary(int off, int len) {
        return new EBinary(data, this.byteOffset() + off, len);
    }
}