com.google.protobuf.CodedOutputStream# writeUInt32 ( ) 源码实例Demo

/**
 * Saves track properties by modifying only file tail.
 */
public void saveProperties(FileDataSource source) throws Exception {
    Track track = source.tracks.get(0);
    // Prepare new properties tail
    ByteBuffer buffer = ByteBuffer.allocate(getSerializedPropertiesSize(track));
    CodedOutputStream output = CodedOutputStream.newInstance(buffer);
    output.writeBytes(FIELD_NAME, ByteString.copyFromUtf8(track.name));
    output.writeUInt32(FIELD_COLOR, track.style.color);
    output.writeFloat(FIELD_WIDTH, track.style.width);
    output.flush();
    // Modify tail of file
    File file = new File(source.path);
    long createTime = file.lastModified();
    RandomAccessFile access = new RandomAccessFile(file, "rw");
    access.setLength(source.propertiesOffset + 1);
    access.seek(source.propertiesOffset);
    access.write(buffer.array());
    access.close();
    //noinspection ResultOfMethodCallIgnored
    file.setLastModified(createTime);
}
 

@Override
public void saveData(OutputStream outputStream, FileDataSource source, @Nullable ProgressListener progressListener) throws Exception {
    if (source.tracks.size() != 1)
        throw new Exception("Only single track can be saved in mtrack format");
    Track track = source.tracks.get(0);
    if (progressListener != null)
        progressListener.onProgressStarted(track.points.size());
    CodedOutputStream output = CodedOutputStream.newInstance(outputStream);
    output.writeUInt32(FIELD_VERSION, VERSION);
    int progress = 0;
    for (Track.TrackPoint point : track.points) {
        output.writeTag(FIELD_POINT, WireFormat.WIRETYPE_LENGTH_DELIMITED);
        output.writeRawVarint32(getSerializedPointSize(point));
        output.writeInt32(FIELD_POINT_LATITUDE, point.latitudeE6);
        output.writeInt32(FIELD_POINT_LONGITUDE, point.longitudeE6);
        output.writeFloat(FIELD_POINT_ALTITUDE, point.elevation);
        output.writeFloat(FIELD_POINT_SPEED, point.speed);
        output.writeFloat(FIELD_POINT_BEARING, point.bearing);
        output.writeFloat(FIELD_POINT_ACCURACY, point.accuracy);
        output.writeUInt64(FIELD_POINT_TIMESTAMP, point.time);
        if (!point.continuous)
            //noinspection ConstantConditions
            output.writeBool(8, point.continuous);
        progress++;
        if (progressListener != null)
            progressListener.onProgressChanged(progress);
    }
    output.writeBytes(FIELD_NAME, ByteString.copyFromUtf8(track.name));
    output.writeUInt32(FIELD_COLOR, track.style.color);
    output.writeFloat(FIELD_WIDTH, track.style.width);
    output.flush();
    outputStream.close();
    if (progressListener != null)
        progressListener.onProgressFinished();
}
 

private void writeTo(FieldInfo fieldInfo, Object value, CodedOutputStream out) throws IOException {
	FieldType fieldType = fieldInfo.getFieldType();
	int order = fieldInfo.getOrder();

	if (value instanceof List) {
		// if check list
		CodedConstant.writeToList(out, order, fieldType, (List) value);
		return;
	}

	switch (fieldType) {
	case DOUBLE:
		out.writeDouble(order, (Double) value);
		break;
	case BYTES:
		ByteString bytes = ByteString.copyFrom((byte[]) value);
		out.writeBytes(order, bytes);
		break;
	case STRING:
		ByteString string = ByteString.copyFromUtf8(value.toString());
		out.writeBytes(order, string);
		break;
	case BOOL:
		out.writeBool(order, (Boolean) value);
		break;
	case FIXED32:
		out.writeFixed32(order, (Integer) value);
		break;
	case SFIXED32:
		out.writeSFixed32(order, (Integer) value);
		break;
	case SINT32:
		out.writeSInt32(order, (Integer) value);
		break;
	case INT32:
		out.writeInt32(order, (Integer) value);
		break;
	case UINT32:
		out.writeUInt32(order, (Integer) value);
		break;
	case FIXED64:
		out.writeFixed64(order, (Long) value);
		break;
	case SFIXED64:
		out.writeSFixed64(order, (Long) value);
		break;
	case SINT64:
		out.writeSInt64(order, (Long) value);
		break;
	case INT64:
		out.writeInt64(order, (Long) value);
		break;
	case UINT64:
		out.writeUInt64(order, (Long) value);
		break;
	case ENUM:
		int i;
		i = getEnumValue(value);
		out.writeEnum(order, i);
		break;
	case FLOAT:
		out.writeFloat(order, (Float) value);
		break;
	case OBJECT:
		Class c = value.getClass();
		ReflectiveCodec codec = new ReflectiveCodec(c);
		out.writeRawVarint32(CodedConstant.makeTag(order, WireFormat.WIRETYPE_LENGTH_DELIMITED));
		out.writeRawVarint32(codec.size(value));
		codec.writeTo(value, out);
		break;
	default:
		throw new IOException("Unknown field type on field '" + fieldInfo.getField().getName() + "'");
	}

}
 

/**
 * Write object to byte array by {@link FieldType}
 * 
 * @param out
 * @param order
 * @param type
 * @param o
 * @throws IOException
 */
public static void writeObject(CodedOutputStream out, int order, FieldType type, Object o, boolean list)
        throws IOException {
    if (o == null) {
        return;
    }

    if (type == FieldType.OBJECT) {

        Class cls = o.getClass();
        Codec target = ProtobufProxy.create(cls);

        out.writeRawVarint32(makeTag(order, WireFormat.WIRETYPE_LENGTH_DELIMITED));
        out.writeRawVarint32(target.size(o));

        target.writeTo(o, out);
        return;
    }

    if (type == FieldType.BOOL) {
        out.writeBool(order, (Boolean) o);
    } else if (type == FieldType.BYTES) {
        byte[] bb = (byte[]) o;
        out.writeBytes(order, ByteString.copyFrom(bb));
    } else if (type == FieldType.DOUBLE) {
        out.writeDouble(order, (Double) o);
    } else if (type == FieldType.FIXED32) {
        out.writeFixed32(order, (Integer) o);
    } else if (type == FieldType.FIXED64) {
        out.writeFixed64(order, (Long) o);
    } else if (type == FieldType.FLOAT) {
        out.writeFloat(order, (Float) o);
    } else if (type == FieldType.INT32) {
        out.writeInt32(order, (Integer) o);
    } else if (type == FieldType.INT64) {
        out.writeInt64(order, (Long) o);
    } else if (type == FieldType.SFIXED32) {
        out.writeSFixed32(order, (Integer) o);
    } else if (type == FieldType.SFIXED64) {
        out.writeSFixed64(order, (Long) o);
    } else if (type == FieldType.SINT32) {
        out.writeSInt32(order, (Integer) o);
    } else if (type == FieldType.SINT64) {
        out.writeSInt64(order, (Long) o);
    } else if (type == FieldType.STRING) {
        out.writeBytes(order, ByteString.copyFromUtf8(String.valueOf(o)));
    } else if (type == FieldType.UINT32) {
        out.writeUInt32(order, (Integer) o);
    } else if (type == FieldType.UINT64) {
        out.writeUInt64(order, (Long) o);
    } else if (type == FieldType.ENUM) {
        int value = 0;
        if (o instanceof EnumReadable) {
            value = ((EnumReadable) o).value();
        } else if (o instanceof Enum) {
            value = ((Enum) o).ordinal();
        }
        out.writeEnum(order, value);
    }
}