feat: add plan execution behavior

core/src/main/java/io/substrait/dsl/SubstraitBuilder.java

@@ -16,7 +16,9 @@
 import io.substrait.extension.DefaultExtensionCatalog;
 import io.substrait.extension.SimpleExtension;
 import io.substrait.function.ToTypeString;
+import io.substrait.plan.ImmutableExecutionBehavior;
 import io.substrait.plan.Plan;
+import io.substrait.plan.Plan.ExecutionBehavior.VariableEvaluationMode;
 import io.substrait.relation.AbstractWriteRel;
 import io.substrait.relation.Aggregate;
 import io.substrait.relation.Aggregate.Measure;
@@ -1540,13 +1542,54 @@ public Plan.Root root(Rel rel) {
   }
 
   /**
-   * Creates a plan from a plan root.
+   * Creates a plan from a plan root with default execution behavior.
+   *
+   * <p>The plan is created with {@link VariableEvaluationMode#PER_PLAN} as the default variable
+   * evaluation mode. To specify a custom execution behavior, use {@link
+   * #plan(Plan.ExecutionBehavior, Plan.Root)} instead.
    *
    * @param root the plan root
    * @return a new {@link Plan}
    */
   public Plan plan(Plan.Root root) {
-    return Plan.builder().addRoots(root).build();
+    return plan(
+        ImmutableExecutionBehavior.builder()
+            .variableEvaluationMode(VariableEvaluationMode.PER_PLAN)
+            .build(),
+        root);
+  }
+
+  /**
+   * Creates a plan from a plan root with custom execution behavior.
+   *
+   * @param executionBehavior the execution behavior for the plan
+   * @param root the plan root
+   * @return a new {@link Plan}
+   */
+  public Plan plan(Plan.ExecutionBehavior executionBehavior, Plan.Root root) {
+    return Plan.builder().executionBehavior(executionBehavior).addRoots(root).build();
+  }
+
+  /**
+   * Creates a plan from multiple plan roots with custom execution behavior.
+   *
+   * @param executionBehavior the execution behavior for the plan
+   * @param roots the plan roots
+   * @return a new {@link Plan}
+   */
+  public Plan plan(Plan.ExecutionBehavior executionBehavior, Plan.Root... roots) {
+    return Plan.builder().executionBehavior(executionBehavior).roots(Arrays.asList(roots)).build();
+  }
+
+  /**
+   * Creates a plan from multiple plan roots with custom execution behavior.
+   *
+   * @param executionBehavior the execution behavior for the plan
+   * @param roots the plan roots as an iterable
+   * @return a new {@link Plan}
+   */
+  public Plan plan(Plan.ExecutionBehavior executionBehavior, Iterable<Plan.Root> roots) {
+    return Plan.builder().executionBehavior(executionBehavior).roots(roots).build();
   }
 
   /**

core/src/main/java/io/substrait/plan/Plan.java

@@ -21,6 +21,34 @@ public Version getVersion() {
 
   public abstract Optional<AdvancedExtension> getAdvancedExtension();
 
+  public abstract ExecutionBehavior getExecutionBehavior();
+
+  /**
+   * Validates that the execution behavior is properly configured.
+   *
+   * <p>This validation method ensures that:
+   *
+   * <ul>
+   *   <li>The {@link ExecutionBehavior} field is present (not null or empty) - ExecutionBehavior is
+   *       a required field
+   *   <li>The {@link ExecutionBehavior.VariableEvaluationMode} is set to a valid value (not {@link
+   *       ExecutionBehavior.VariableEvaluationMode#UNSPECIFIED})
+   * </ul>
+   *
+   * @throws IllegalArgumentException if the execution behavior is not present, or if the variable
+   *     evaluation mode is set to {@link ExecutionBehavior.VariableEvaluationMode#UNSPECIFIED}
+   */
+  @Value.Check
+  protected void check() {
+    ExecutionBehavior behavior = getExecutionBehavior();
+    if (behavior.getVariableEvaluationMode()
+        == ExecutionBehavior.VariableEvaluationMode.UNSPECIFIED) {
+      throw new IllegalArgumentException(
+          "ExecutionBehavior requires a specified VariableEvaluationMode, but got: "
+              + behavior.getVariableEvaluationMode());
+    }
+  }
+
   public static ImmutablePlan.Builder builder() {
     return ImmutablePlan.builder();
   }
@@ -69,4 +97,40 @@ public static ImmutableRoot.Builder builder() {
       return ImmutableRoot.builder();
     }
   }
+
+  @Value.Immutable
+  public abstract static class ExecutionBehavior {
+    public abstract VariableEvaluationMode getVariableEvaluationMode();
+
+    public static ImmutableExecutionBehavior.Builder builder() {
+      return ImmutableExecutionBehavior.builder();
+    }
+
+    public enum VariableEvaluationMode {
+      UNSPECIFIED(
+          io.substrait.proto.ExecutionBehavior.VariableEvaluationMode
+              .VARIABLE_EVALUATION_MODE_UNSPECIFIED),
+      PER_PLAN(
+          io.substrait.proto.ExecutionBehavior.VariableEvaluationMode
+              .VARIABLE_EVALUATION_MODE_PER_PLAN),
+      PER_RECORD(
+          io.substrait.proto.ExecutionBehavior.VariableEvaluationMode
+              .VARIABLE_EVALUATION_MODE_PER_RECORD);
+
+      private final io.substrait.proto.ExecutionBehavior.VariableEvaluationMode proto;
+
+      VariableEvaluationMode(io.substrait.proto.ExecutionBehavior.VariableEvaluationMode proto) {
+        this.proto = proto;
+      }
+
+      /**
+       * Converts this variable evaluation mode to its protobuf representation.
+       *
+       * @return the protobuf representation
+       */
+      public io.substrait.proto.ExecutionBehavior.VariableEvaluationMode toProto() {
+        return proto;
+      }
+    }
+  }
 }

core/src/main/java/io/substrait/plan/PlanProtoConverter.java

@@ -4,6 +4,7 @@
 import io.substrait.extension.ExtensionCollector;
 import io.substrait.extension.ExtensionProtoConverter;
 import io.substrait.extension.SimpleExtension.ExtensionCollection;
+import io.substrait.proto.ExecutionBehavior;
 import io.substrait.proto.Plan;
 import io.substrait.proto.PlanRel;
 import io.substrait.proto.Rel;
@@ -61,6 +62,13 @@ public PlanProtoConverter(
     this.extensionProtoConverter = extensionProtoConverter;
   }
 
+  /**
+   * Converts a {@link io.substrait.plan.Plan} object to its protobuf representation.
+   *
+   * @param plan the Plan object to convert, must not be null
+   * @return the protobuf Plan representation
+   * @throws IllegalArgumentException if the plan contains invalid data
+   */
   public Plan toProto(final io.substrait.plan.Plan plan) {
     final List<PlanRel> planRels = new ArrayList<>();
     final ExtensionCollector functionCollector = new ExtensionCollector(extensionCollection);
@@ -97,6 +105,26 @@ public Plan toProto(final io.substrait.plan.Plan plan) {
 
     builder.setVersion(versionBuilder);
 
+    // Set execution behavior
+    builder.setExecutionBehavior(toProtoExecutionBehavior(plan.getExecutionBehavior()));
+
     return builder.build();
   }
+
+  /**
+   * Converts an {@link io.substrait.plan.Plan.ExecutionBehavior} to its protobuf representation.
+   *
+   * <p>This method converts the execution behavior configuration, including the variable evaluation
+   * mode, from the POJO representation to the protobuf format.
+   *
+   * @param executionBehavior the ExecutionBehavior to convert, must not be null
+   * @return the protobuf ExecutionBehavior representation
+   * @throws IllegalArgumentException if the variable evaluation mode is unknown
+   */
+  private ExecutionBehavior toProtoExecutionBehavior(
+      final io.substrait.plan.Plan.ExecutionBehavior executionBehavior) {
+    return ExecutionBehavior.newBuilder()
+        .setVariableEvalMode(executionBehavior.getVariableEvaluationMode().toProto())
+        .build();
+  }
 }

core/src/main/java/io/substrait/plan/ProtoPlanConverter.java

@@ -5,6 +5,8 @@
 import io.substrait.extension.ImmutableExtensionLookup;
 import io.substrait.extension.ProtoExtensionConverter;
 import io.substrait.extension.SimpleExtension.ExtensionCollection;
+import io.substrait.plan.Plan.ExecutionBehavior;
+import io.substrait.plan.Plan.ExecutionBehavior.VariableEvaluationMode;
 import io.substrait.proto.PlanRel;
 import io.substrait.relation.ProtoRelConverter;
 import io.substrait.relation.Rel;
@@ -66,6 +68,21 @@ protected ProtoRelConverter getProtoRelConverter(final ExtensionLookup functionL
     return new ProtoRelConverter(functionLookup, this.extensionCollection, protoExtensionConverter);
   }
 
+  /**
+   * Converts a protobuf {@link io.substrait.proto.Plan} to a {@link Plan} POJO.
+   *
+   * <p><b>Note:</b> Execution behavior is optional in the protobuf message, but the {@link Plan}
+   * POJO requires it. Conversion handles a missing execution behavior based on the plan version:
+   *
+   * <p><b>Note:</b> If {@code Plan.ExecutionBehavior.VariableEvaluationMode} is not set, it will be
+   * defaulted to {@code VARIABLE_EVALUATION_MODE_PER_PLAN}. Once other producers populate this
+   * field correctly, this compatibility workaround will be removed.
+   *
+   * @param plan the protobuf Plan to convert, must not be null
+   * @return the converted Plan POJO
+   * @throws IllegalArgumentException if the plan contains invalid data or if the execution behavior
+   *     validation fails
+   */
   public Plan from(io.substrait.proto.Plan plan) {
     ExtensionLookup functionLookup = ImmutableExtensionLookup.builder().from(plan).build();
     ProtoRelConverter relConverter = getProtoRelConverter(functionLookup);
@@ -92,15 +109,84 @@ public Plan from(io.substrait.proto.Plan plan) {
       versionBuilder.producer(Optional.of(plan.getVersion().getProducer()));
     }
 
-    return Plan.builder()
-        .roots(roots)
-        .expectedTypeUrls(plan.getExpectedTypeUrlsList())
-        .advancedExtension(
-            Optional.ofNullable(
-                plan.hasAdvancedExtensions()
-                    ? protoExtensionConverter.fromProto(plan.getAdvancedExtensions())
-                    : null))
-        .version(versionBuilder.build())
+    ImmutablePlan.Builder planBuilder =
+        Plan.builder()
+            .roots(roots)
+            .expectedTypeUrls(plan.getExpectedTypeUrlsList())
+            .advancedExtension(
+                Optional.ofNullable(
+                    plan.hasAdvancedExtensions()
+                        ? protoExtensionConverter.fromProto(plan.getAdvancedExtensions())
+                        : null))
+            .version(versionBuilder.build());
+
+    // Set execution behavior (required field)
+    if (plan.hasExecutionBehavior()) {
+      planBuilder.executionBehavior(fromProtoExecutionBehavior(plan.getExecutionBehavior()));
+    } else {
+      // Set default ExecutionBehavior for older plans that don't have it
+      planBuilder.executionBehavior(
+          ExecutionBehavior.builder()
+              .variableEvaluationMode(VariableEvaluationMode.PER_PLAN)
+              .build());
+    }
+
+    return planBuilder.build();
+  }
+
+  /**
+   * Converts a protobuf {@link io.substrait.proto.ExecutionBehavior} to its POJO representation.
+   *
+   * <p>This method converts the execution behavior configuration from the protobuf format to the
+   * POJO representation, including the variable evaluation mode.
+   *
+   * @param executionBehavior the protobuf ExecutionBehavior to convert, must not be null
+   * @return the POJO ExecutionBehavior representation
+   * @throws IllegalArgumentException if the variable evaluation mode is unknown or UNRECOGNIZED
+   */
+  private io.substrait.plan.Plan.ExecutionBehavior fromProtoExecutionBehavior(
+      final io.substrait.proto.ExecutionBehavior executionBehavior) {
+    return io.substrait.plan.Plan.ExecutionBehavior.builder()
+        .variableEvaluationMode(
+            fromProtoVariableEvaluationMode(executionBehavior.getVariableEvalMode()))
         .build();
   }
+
+  /**
+   * Converts a protobuf {@link io.substrait.proto.ExecutionBehavior.VariableEvaluationMode} to its
+   * POJO representation.
+   *
+   * <p>Supported modes:
+   *
+   * <ul>
+   *   <li>{@link
+   *       io.substrait.proto.ExecutionBehavior.VariableEvaluationMode#VARIABLE_EVALUATION_MODE_UNSPECIFIED}
+   *       - Unspecified mode (will cause validation failure in Plan)
+   *   <li>{@link
+   *       io.substrait.proto.ExecutionBehavior.VariableEvaluationMode#VARIABLE_EVALUATION_MODE_PER_PLAN}
+   *       - Variables are evaluated once per plan execution
+   *   <li>{@link
+   *       io.substrait.proto.ExecutionBehavior.VariableEvaluationMode#VARIABLE_EVALUATION_MODE_PER_RECORD}
+   *       - Variables are evaluated for each record
+   * </ul>
+   *
+   * @param mode the protobuf VariableEvaluationMode to convert, must not be null
+   * @return the POJO VariableEvaluationMode representation
+   * @throws IllegalArgumentException if the mode is UNRECOGNIZED or not supported
+   */
+  private io.substrait.plan.Plan.ExecutionBehavior.VariableEvaluationMode
+      fromProtoVariableEvaluationMode(
+          final io.substrait.proto.ExecutionBehavior.VariableEvaluationMode mode) {
+    switch (mode) {
+      case VARIABLE_EVALUATION_MODE_UNSPECIFIED:
+        return io.substrait.plan.Plan.ExecutionBehavior.VariableEvaluationMode.UNSPECIFIED;
+      case VARIABLE_EVALUATION_MODE_PER_PLAN:
+        return io.substrait.plan.Plan.ExecutionBehavior.VariableEvaluationMode.PER_PLAN;
+      case VARIABLE_EVALUATION_MODE_PER_RECORD:
+        return io.substrait.plan.Plan.ExecutionBehavior.VariableEvaluationMode.PER_RECORD;
+      case UNRECOGNIZED:
+      default:
+        throw new IllegalArgumentException("Unknown VariableEvaluationMode: " + mode);
+    }
+  }
 }