convert to config

convert to config

https://github.com/apache/wayang/blob/560fcfc56ec251ca0bbf61b3a7279d57bf71ea62/wayang-plugins/wayang-ml/src/main/java/org/apache/wayang/ml/encoding/TreeEncoder.java#L61

```java

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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.wayang.ml.encoding;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Queue;

import org.apache.wayang.core.api.exception.WayangException;
import org.apache.wayang.core.optimizer.OptimizationContext;
import org.apache.wayang.core.optimizer.enumeration.PlanImplementation;
import org.apache.wayang.core.plan.executionplan.ExecutionTask;
import org.apache.wayang.core.plan.wayangplan.ExecutionOperator;
import org.apache.wayang.core.plan.wayangplan.InputSlot;
import org.apache.wayang.core.plan.wayangplan.Operator;
import org.apache.wayang.core.plan.wayangplan.OperatorAlternative;
import org.apache.wayang.core.plan.wayangplan.OutputSlot;
import org.apache.wayang.core.plan.wayangplan.WayangPlan;
import org.apache.wayang.core.platform.Junction;

public class TreeEncoder {
private final OneHotMappings mappings;

public TreeEncoder(final OneHotMappings mappings) {
this.mappings = mappings;
}

public OneHotMappings getMappings() {
return this.mappings;
}

public TreeNode encode(final PlanImplementation plan) {
final List result = new ArrayList();

final HashMap> tree = new HashMap<>();
final List sinks = plan.getOperators().stream().filter(Operator::isSink).toList();

final Map, Junction> junctions = plan.getJunctions();

// TODO: convert to config
final boolean encodeIds = false;

for (final Operator sink : sinks) {
final TreeNode sinkNode = traversePIOperator(sink, plan.getOptimizationContext(), encodeIds, junctions,
tree);
result.add(sinkNode);
}

if (result.size() == 0) {
return null;
}

final TreeNode resultNode = result.get(0);
resultNode.rebalance();

return resultNode;
}

public TreeNode encode(final WayangPlan plan, final OptimizationContext optimizationContext,
final boolean encodeIds) {
final List result = new ArrayList();
plan.prune();

final HashMap> tree = new HashMap<>();
final Collection sinks = plan.getSinks();

for (final Operator sink : sinks) {
final TreeNode sinkNode = traverse(sink, tree, optimizationContext, encodeIds);
result.add(sinkNode);
}

if (result.size() == 0) {
return null;
}

assert result.size() == 1 : "result size was not 1";

final TreeNode resultNode = result.get(0);

// rebalance to make it a guaranteed binary tree
resultNode.rebalance();

return resultNode;
}

private TreeNode traversePIOperator(final Operator current, final OptimizationContext optimizationContext,
final boolean encodeIds, final Map, Junction> junctions,
final HashMap> visited) {
if (visited.containsKey(current)) {
return null;
}

final TreeNode currentNode = new TreeNode();

if (current.isAlternative()) {
final Operator original = ((OperatorAlternative) current).getAlternatives().get(0).getContainedOperators()
.stream().findFirst()
.orElseThrow(() -> new WayangException("Operator could not be retrieved from Alternatives"));
mappings.addOriginalOperator(original);

currentNode.encoded = OneHotEncoder.encodeOperator(original, optimizationContext, encodeIds);
} else {
mappings.addOriginalOperator(current);

if (current.isExecutionOperator()) {
currentNode.encoded = OneHotEncoder.encodeOperator((ExecutionOperator) current, optimizationContext,
encodeIds);
} else {
currentNode.encoded = OneHotEncoder.encodeOperator(current, optimizationContext, encodeIds);
}
}

final Collection currentJunctions = junctions.values().stream().filter(junction -> {
for (final InputSlot input : current.getAllInputs()) {
if (junction.getTargetInputs().contains(input)) {
return true;
}
}

return false;
}).toList();

final Collection inputs = currentJunctions.stream().map(Junction::getSourceOperator)
.toList();

for (final Operator input : inputs) {
TreeNode next;
final Collection conversions = currentJunctions.stream()
.filter(junction -> junction.getSourceOperator() == input)
.flatMap(junction -> junction.getConversionTasks().stream()).toList();

// fit conversions in between current and its inputs
if (conversions.size() > 0) {
final Queue conversionQueue = new LinkedList<>();
conversionQueue.addAll(conversions);

next = traverseWithNext(conversionQueue, junctions, visited, input, optimizationContext, encodeIds);
} else {
next = traversePIOperator(input, optimizationContext, encodeIds, junctions, visited);
}

if (currentNode.left == null) {
currentNode.left = next;
} else {
currentNode.right = next;
}
}

return currentNode;
}

private TreeNode traverseWithNext(final Queue conversions,
final Map, Junction> junctions, final HashMap> visited,
final Operator next, final OptimizationContext optimizationContext, final boolean encodeIds) {
if (visited.containsKey(next)) {
return null;
}

if (conversions.isEmpty()) {
return traversePIOperator(next, optimizationContext, encodeIds, junctions, visited);
}

final ExecutionTask currentTask = conversions.poll();
final ExecutionOperator current = currentTask.getOperator();
final TreeNode currentNode = new TreeNode();

if (current.isAlternative()) {
final Operator original = ((OperatorAlternative) current).getAlternatives().get(0).getContainedOperators()
.stream().findFirst()
.orElseThrow(() -> new WayangException("Operator could not be retrieved from Alternatives"));
mappings.addOriginalOperator(original);

currentNode.encoded = OneHotEncoder.encodeOperator(original, optimizationContext, encodeIds);
currentNode.operator = original;
} else {
mappings.addOriginalOperator(current);
currentNode.operator = current;

if (current.isExecutionOperator()) {
currentNode.encoded = OneHotEncoder.encodeOperator((ExecutionOperator) current, optimizationContext,
encodeIds);
} else {
currentNode.encoded = OneHotEncoder.encodeOperator(current, optimizationContext, encodeIds);
}
}

final TreeNode nextNode = traverseWithNext(conversions, junctions, visited, next, optimizationContext,
encodeIds);

if (currentNode.left == null) {
currentNode.left = nextNode;
} else {
currentNode.right = nextNode;
}

return currentNode;
}

private TreeNode traverse(final Operator current, final HashMap> visited,
final OptimizationContext optimizationContext, final boolean encodeIds) {
if (visited.containsKey(current)) {
return null;
}

final TreeNode currentNode = new TreeNode();

if (current.isAlternative()) {
final Operator original = ((OperatorAlternative) current).getAlternatives().get(0).getContainedOperators()
.stream().findFirst()
.orElseThrow(() -> new WayangException("Operator could not be retrieved from Alternatives"));
mappings.addOriginalOperator(original);

currentNode.encoded = OneHotEncoder.encodeOperator(original, optimizationContext, encodeIds);
currentNode.operator = original;
} else {
mappings.addOriginalOperator(current);
currentNode.operator = current;

if (current.isExecutionOperator()) {
currentNode.encoded = OneHotEncoder.encodeOperator((ExecutionOperator) current, optimizationContext,
encodeIds);
} else {
currentNode.encoded = OneHotEncoder.encodeOperator(current, optimizationContext, encodeIds);
}
}

// Add for later reconstruction in TreeDecoder
final List inputs = Arrays.stream(current.getAllInputs()).filter(input -> input.getOccupant() != null)
.map(input -> input.getOccupant().getOwner()).toList();

for (final Operator input : inputs) {
final TreeNode next = traverse(input, visited, optimizationContext, encodeIds);

if (currentNode.getLeft() == null) {
currentNode.left = next;
} else {
currentNode.right = next;
}
}

return currentNode;
}

}

```

6249cbd2314c64aaf320b1b14c80b51013289b9c

Start in wayang-plugins/wayang-ml/src/main/java/org/apache/wayang/ml/encoding/TreeEncoder.java at the TODO near line 61. Compare the hardcoded encodeIds value in encode(PlanImplementation) with the boolean parameter used by the other encode overload, then trace the surrounding configuration approach. Done means the setting is controlled through configuration rather than a fixed local value.

Written by the indexing model from the issue text.