mbeckerle commented on code in PR #1176: URL: https://github.com/apache/daffodil/pull/1176#discussion_r1516107626
########## daffodil-runtime1/src/main/scala/org/apache/daffodil/runtime1/layers/LayerDriver.scala: ########## @@ -0,0 +1,227 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You 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 org.apache.daffodil.runtime1.layers + +import java.io.FilterInputStream +import java.io.FilterOutputStream +import java.io.InputStream +import java.io.OutputStream + +import org.apache.daffodil.io.DataInputStream.Mark +import org.apache.daffodil.io.DataOutputStream +import org.apache.daffodil.io.DirectOrBufferedDataOutputStream +import org.apache.daffodil.io.FormatInfo +import org.apache.daffodil.io.InputSourceDataInputStream +import org.apache.daffodil.lib.exceptions.Assert +import org.apache.daffodil.lib.schema.annotation.props.gen.BitOrder +import org.apache.daffodil.lib.util.Maybe +import org.apache.daffodil.lib.util.Maybe.Nope +import org.apache.daffodil.lib.util.Maybe.One +import org.apache.daffodil.lib.util.Misc +import org.apache.daffodil.runtime1.layers.api.Layer +import org.apache.daffodil.runtime1.processors.unparsers.UState + +import passera.unsigned.ULong + +/** + * Driving mechanism that incorporates a layer at runtime to transform the data stream. + * + * A layer driver is created at runtime as part of a single parse/unparse call. + * Hence, they can be stateful without causing thread-safety issues. + */ +class LayerDriver( + layerRuntimeData: LayerRuntimeData, + layer: Layer, + layerVarsRuntime: LayerVarsRuntime, +) { + + private def wrapJavaInputStream( + s: InputSourceDataInputStream, + layerRuntimeImpl: LayerRuntimeImpl, + ): InputStream = + new JavaIOInputStream(s, layerRuntimeImpl.finfo) + + private def wrapJavaOutputStream( + s: DataOutputStream, + layerRuntimeImpl: LayerRuntimeImpl, + ): OutputStream = + new JavaIOOutputStream(s, layer, layerRuntimeImpl, layerVarsRuntime) + + /** + * Override these if we ever have transformers that don't have these + * requirements. + */ + val mandatoryLayerAlignmentInBits: Int = 8 + + final def addInputLayer( + s: InputSourceDataInputStream, + layerRuntimeImpl: LayerRuntimeImpl, + ): InputSourceDataInputStream = { + val jis = wrapJavaInputStream(s, layerRuntimeImpl) + val decodedInputStream = + new AssuredCloseInputStream(layer.wrapLayerInput(jis, layerRuntimeImpl), jis) + val newDIS = InputSourceDataInputStream(decodedInputStream) + newDIS.cst.setPriorBitOrder( + BitOrder.MostSignificantBitFirst, + ) // must initialize priorBitOrder + newDIS.setDebugging(s.areDebugging) + newDIS + } + + /** + * Parsing works as a tree traversal, so when the parser unwinds from + * parsing the layer we can invoke this to handle cleanups, and + * finalization issues like assigning the result variables + */ + final def removeInputLayer( + s: InputSourceDataInputStream, + layerRuntimeImpl: LayerRuntimeImpl, + ): Unit = { + layerVarsRuntime.callGettersToPopulateResultVars(layer, layerRuntimeImpl) Review Comment: I think I would prefer one setter for all params. Only a zero-arg default constructor is needed then. But we still need to compute the call to the setter at schema compile time, which checks the types and number and names of the parameters against the variable definintions. It's much closer to the java-beans approach, ie., 100% of making sure all the parameters are correct is on the user's back, vs the constructor approach, but both are viable. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
