wayang-commons/wayang-core/src/main/java/org/apache/wayang/core/plan/wayangplan/InputSlot.java - incubator-wayang - Git at Google

 /*
  * 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.wayang.core.plan.wayangplan;

 import org.apache.wayang.core.types.DataSetType;

 import java.util.List;

 /**
  * An input slot declares an input of an {@link Operator}.
  *
  * @param <T> see {@link Slot}
  */
 public class InputSlot<T> extends Slot<T> {

     /**
      * Output slot of another operator that is connected to this input slot.
      */
     private OutputSlot<T> occupant;

     /**
      * Tells whether this instance represents a broadcasted input.
      */
     private final boolean isBroadcast;

     /**
      * Copy the {@link InputSlot}s of a given {@link Operator}.
      */
     public static void mock(Operator template, Operator mock) {
         mock(template, mock, true);
     }

     /**
      * Copy the {@link InputSlot}s of a given {@link Operator}.
      */
     public static void mock(Operator template, Operator mock, boolean isKeepBroadcastStatus) {
         if (template.getNumInputs() != mock.getNumInputs()) {
             throw new IllegalArgumentException("Cannot mock inputs: Mismatching number of inputs.");
         }

         InputSlot[] mockSlots = mock.getAllInputs();
         for (int i = 0; i < template.getNumInputs(); i++) {
             mockSlots[i] = isKeepBroadcastStatus ?
                     template.getInput(i).copyFor(mock) :
                     template.getInput(i).copyAsNonBroadcastFor(mock);
         }
     }

     /**
      * Copy the {@link InputSlot}s to a given {@link Operator}.
      */
     public static void mock(List<InputSlot<?>> inputSlots, Operator mock, boolean isKeepBroadcastStatus) {
         if (inputSlots.size() != mock.getNumInputs()) {
             throw new IllegalArgumentException("Cannot mock inputs: Mismatching number of inputs.");
         }

         InputSlot[] mockSlots = mock.getAllInputs();
         int i = 0;
         for (InputSlot<?> inputSlot : inputSlots) {
             mockSlots[i++] = isKeepBroadcastStatus ?
                     inputSlot.copyFor(mock) :
                     inputSlot.copyAsNonBroadcastFor(mock);
         }
     }

     /**
      * Take the input connections away from one operator and give them to another one.
      */
     public static void stealConnections(Operator victim, Operator thief) {
         if (victim.getNumInputs() != thief.getNumInputs()) {
             throw new IllegalArgumentException("Cannot steal inputs: Mismatching number of inputs.");
         }

         for (int i = 0; i < victim.getNumInputs(); i++) {
             thief.getInput(i).unchecked().stealOccupant(victim.getInput(i).unchecked());
         }
     }

     /**
      * Takes away the occupant {@link OutputSlot} of the {@code victim} and connects it to this instance.
      */
     public void stealOccupant(InputSlot<T> victim) {
         if (victim.getOccupant() == null) return;
         assert this.getOccupant() == null : String.format(
                 "%s cannot steal %s's occuppant %s, because there already is %s.",
                 this, victim, victim.getOccupant(), this.getOccupant()
         );
         final OutputSlot<T> occupant = victim.getOccupant();
         if (occupant != null) {
             occupant.disconnectFrom(victim);
             occupant.connectTo(this);
         }
     }

     /**
      * Creates a new instance that imitates the given {@code blueprint}, but for a different {@code owner}.
      */
     public InputSlot(Slot<T> blueprint, Operator owner) {
         this(blueprint.getName(), owner, blueprint.getType());
     }

     /**
      * Creates a new instance that imitates the given {@code blueprint}, but for a different {@code owner}.
      */
     public InputSlot(InputSlot<T> blueprint, Operator owner) {
         this(blueprint.getName(), owner, blueprint.isBroadcast(), blueprint.getType());
     }

     /**
      * Creates a new, non-broadcast instance.
      */
     public InputSlot(String name, Operator owner, DataSetType<T> type) {
         this(name, owner, false, type);
     }

     /**
      * Creates a new instance.
      */
     public InputSlot(String name, Operator owner, boolean isBroadcast, DataSetType<T> type) {
         super(name, owner, type);
         this.isBroadcast = isBroadcast;
     }

     /**
      * Shortcut for {@link #InputSlot(Slot, Operator)}
      */
     public InputSlot<T> copyFor(Operator owner) {
         return new InputSlot<>(this, owner);
     }

     /**
      * As {@link #copyFor(Operator)}, but ensures that the copy will not be marked as broadcast.
      */
     public InputSlot<T> copyAsNonBroadcastFor(Operator owner) {
         return new InputSlot<>(this.getName(), owner, false, this.getType());
     }

     /**
      * Connects the given {@link OutputSlot}. Consider using the interface of the {@link OutputSlot} instead to
      * keep consistency of connections in the plan.
      *
      * @param outputSlot the output slot to connect to
      * @return this instance
      * @see OutputSlot#connectTo(InputSlot)
      * @see OutputSlot#disconnectFrom(InputSlot)
      */
     InputSlot<T> setOccupant(OutputSlot<T> outputSlot) {
         this.occupant = outputSlot;
         return this;
     }

     public OutputSlot<T> getOccupant() {
         return this.occupant;
     }

     @Override
     public int getIndex() throws IllegalStateException {
         if (this.index != -1) return this.index;

         assert this.getOwner() != null : "This slot has no owner.";
         for (int i = 0; i < this.getOwner().getNumInputs(); i++) {
             if (this.getOwner().getInput(i) == this) {
                 return this.index = i;
             }
         }
         throw new IllegalStateException("Could not find this slot within its owner.");
     }

     @SuppressWarnings("unchecked")
     public InputSlot<Object> unchecked() {
         return (InputSlot<Object>) this;
     }

     /**
      * @return whether this is a broadcast
      */
     public boolean isBroadcast() {
         return this.isBroadcast;
     }

     /**
      * @return whether this instance is designated to close feedback loops (i.e., data flow cycles)
      */
     public boolean isFeedback() {
         return this.getOwner().isFeedbackInput(this);
     }

     /**
      * Notifies this instance that it has been detached from its {@link #occupant}.
      */
     public void notifyDetached() {
         if (this.isBroadcast) {
             // TODO: Consider removing broadacast.
         }
     }

     /**
      * Tells whether this instance is inside of a {@link LoopSubplan} and consumes an {@link OutputSlot} outside
      * of that {@link LoopSubplan}.
      *
      * @return whether above condition is satisfied
      */
     public boolean isLoopInvariant() {
         final Operator owner = this.getOwner();

         // If this is a LoopHeadOperator initial/iteration input, we know that this is not loop invariant.
         if (owner.isLoopHead() && (
                 ((LoopHeadOperator) owner).getLoopBodyInputs().contains(this)
                         || ((LoopHeadOperator) owner).getLoopInitializationInputs().contains(this)
         )) return false;

         // Find the loop this instance is in.
         final LoopSubplan innermostLoop = owner.getInnermostLoop();
         if (innermostLoop == null) return false;

         // Find the adjacent OutputSlot.
         final InputSlot<T> outerInput = owner.getOutermostInputSlot(this);
         final OutputSlot<T> occupant = outerInput.getOccupant();
         if (occupant == null) return false;

         // Check if the adjacent OutputSlot is in a different loop.
         return occupant.getOwner().getInnermostLoop() != innermostLoop;
     }
 }
	/*
	* 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.wayang.core.plan.wayangplan;

	import org.apache.wayang.core.types.DataSetType;

	import java.util.List;

	/**
	* An input slot declares an input of an {@link Operator}.
	*
	* @param <T> see {@link Slot}
	*/
	public class InputSlot<T> extends Slot<T> {

	/**
	* Output slot of another operator that is connected to this input slot.
	*/
	private OutputSlot<T> occupant;

	/**
	* Tells whether this instance represents a broadcasted input.
	*/
	private final boolean isBroadcast;

	/**
	* Copy the {@link InputSlot}s of a given {@link Operator}.
	*/
	public static void mock(Operator template, Operator mock) {
	mock(template, mock, true);
	}

	/**
	* Copy the {@link InputSlot}s of a given {@link Operator}.
	*/
	public static void mock(Operator template, Operator mock, boolean isKeepBroadcastStatus) {
	if (template.getNumInputs() != mock.getNumInputs()) {
	throw new IllegalArgumentException("Cannot mock inputs: Mismatching number of inputs.");
	}

	InputSlot[] mockSlots = mock.getAllInputs();
	for (int i = 0; i < template.getNumInputs(); i++) {
	mockSlots[i] = isKeepBroadcastStatus ?
	template.getInput(i).copyFor(mock) :
	template.getInput(i).copyAsNonBroadcastFor(mock);
	}
	}

	/**
	* Copy the {@link InputSlot}s to a given {@link Operator}.
	*/
	public static void mock(List<InputSlot<?>> inputSlots, Operator mock, boolean isKeepBroadcastStatus) {
	if (inputSlots.size() != mock.getNumInputs()) {
	throw new IllegalArgumentException("Cannot mock inputs: Mismatching number of inputs.");
	}

	InputSlot[] mockSlots = mock.getAllInputs();
	int i = 0;
	for (InputSlot<?> inputSlot : inputSlots) {
	mockSlots[i++] = isKeepBroadcastStatus ?
	inputSlot.copyFor(mock) :
	inputSlot.copyAsNonBroadcastFor(mock);
	}
	}

	/**
	* Take the input connections away from one operator and give them to another one.
	*/
	public static void stealConnections(Operator victim, Operator thief) {
	if (victim.getNumInputs() != thief.getNumInputs()) {
	throw new IllegalArgumentException("Cannot steal inputs: Mismatching number of inputs.");
	}

	for (int i = 0; i < victim.getNumInputs(); i++) {
	thief.getInput(i).unchecked().stealOccupant(victim.getInput(i).unchecked());
	}
	}

	/**
	* Takes away the occupant {@link OutputSlot} of the {@code victim} and connects it to this instance.
	*/
	public void stealOccupant(InputSlot<T> victim) {
	if (victim.getOccupant() == null) return;
	assert this.getOccupant() == null : String.format(
	"%s cannot steal %s's occuppant %s, because there already is %s.",
	this, victim, victim.getOccupant(), this.getOccupant()
	);
	final OutputSlot<T> occupant = victim.getOccupant();
	if (occupant != null) {
	occupant.disconnectFrom(victim);
	occupant.connectTo(this);
	}
	}

	/**
	* Creates a new instance that imitates the given {@code blueprint}, but for a different {@code owner}.
	*/
	public InputSlot(Slot<T> blueprint, Operator owner) {
	this(blueprint.getName(), owner, blueprint.getType());
	}

	/**
	* Creates a new instance that imitates the given {@code blueprint}, but for a different {@code owner}.
	*/
	public InputSlot(InputSlot<T> blueprint, Operator owner) {
	this(blueprint.getName(), owner, blueprint.isBroadcast(), blueprint.getType());
	}

	/**
	* Creates a new, non-broadcast instance.
	*/
	public InputSlot(String name, Operator owner, DataSetType<T> type) {
	this(name, owner, false, type);
	}

	/**
	* Creates a new instance.
	*/
	public InputSlot(String name, Operator owner, boolean isBroadcast, DataSetType<T> type) {
	super(name, owner, type);
	this.isBroadcast = isBroadcast;
	}

	/**
	* Shortcut for {@link #InputSlot(Slot, Operator)}
	*/
	public InputSlot<T> copyFor(Operator owner) {
	return new InputSlot<>(this, owner);
	}

	/**
	* As {@link #copyFor(Operator)}, but ensures that the copy will not be marked as broadcast.
	*/
	public InputSlot<T> copyAsNonBroadcastFor(Operator owner) {
	return new InputSlot<>(this.getName(), owner, false, this.getType());
	}

	/**
	* Connects the given {@link OutputSlot}. Consider using the interface of the {@link OutputSlot} instead to
	* keep consistency of connections in the plan.
	*
	* @param outputSlot the output slot to connect to
	* @return this instance
	* @see OutputSlot#connectTo(InputSlot)
	* @see OutputSlot#disconnectFrom(InputSlot)
	*/
	InputSlot<T> setOccupant(OutputSlot<T> outputSlot) {
	this.occupant = outputSlot;
	return this;
	}

	public OutputSlot<T> getOccupant() {
	return this.occupant;
	}

	@Override
	public int getIndex() throws IllegalStateException {
	if (this.index != -1) return this.index;

	assert this.getOwner() != null : "This slot has no owner.";
	for (int i = 0; i < this.getOwner().getNumInputs(); i++) {
	if (this.getOwner().getInput(i) == this) {
	return this.index = i;
	}
	}
	throw new IllegalStateException("Could not find this slot within its owner.");
	}

	@SuppressWarnings("unchecked")
	public InputSlot<Object> unchecked() {
	return (InputSlot<Object>) this;
	}

	/**
	* @return whether this is a broadcast
	*/
	public boolean isBroadcast() {
	return this.isBroadcast;
	}

	/**
	* @return whether this instance is designated to close feedback loops (i.e., data flow cycles)
	*/
	public boolean isFeedback() {
	return this.getOwner().isFeedbackInput(this);
	}

	/**
	* Notifies this instance that it has been detached from its {@link #occupant}.
	*/
	public void notifyDetached() {
	if (this.isBroadcast) {
	// TODO: Consider removing broadacast.
	}
	}

	/**
	* Tells whether this instance is inside of a {@link LoopSubplan} and consumes an {@link OutputSlot} outside
	* of that {@link LoopSubplan}.
	*
	* @return whether above condition is satisfied
	*/
	public boolean isLoopInvariant() {
	final Operator owner = this.getOwner();

	// If this is a LoopHeadOperator initial/iteration input, we know that this is not loop invariant.
	if (owner.isLoopHead() && (
	((LoopHeadOperator) owner).getLoopBodyInputs().contains(this)
	\|\| ((LoopHeadOperator) owner).getLoopInitializationInputs().contains(this)
	)) return false;

	// Find the loop this instance is in.
	final LoopSubplan innermostLoop = owner.getInnermostLoop();
	if (innermostLoop == null) return false;

	// Find the adjacent OutputSlot.
	final InputSlot<T> outerInput = owner.getOutermostInputSlot(this);
	final OutputSlot<T> occupant = outerInput.getOccupant();
	if (occupant == null) return false;

	// Check if the adjacent OutputSlot is in a different loop.
	return occupant.getOwner().getInnermostLoop() != innermostLoop;
	}
	}