1 files changed, 109 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/planning/operations/PProject.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/planning/operations/PProject.java
new file mode 100644
index 00000000..d0539b2c
--- /dev/null
+++ b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/planning/operations/PProject.java
@@ -0,0 +1,109 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2014, Bergmann Gabor, Istvan Rath and Daniel Varro
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package tools.refinery.viatra.runtime.matchers.planning.operations;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import tools.refinery.viatra.runtime.matchers.planning.SubPlan;
+import tools.refinery.viatra.runtime.matchers.psystem.PConstraint;
+import tools.refinery.viatra.runtime.matchers.psystem.PVariable;
+import tools.refinery.viatra.runtime.matchers.util.Preconditions;
+
+/**
+ * Represents a projection of a single parent SubPlan onto a limited set of variables.
+ * <p> May optionally prescribe an ordering of variables (List, as opposed to Set).
+ * 
+ * @author Bergmann Gabor
+ *
+ */
+public class PProject extends POperation {
+
+    private Collection<PVariable> toVariables;
+    private boolean ordered;
+        
+    
+    public PProject(Set<PVariable> toVariables) {
+        super();
+        this.toVariables = toVariables;
+        this.ordered = false;
+    }
+    public PProject(List<PVariable> toVariables) {
+        super();
+        this.toVariables = toVariables;
+        this.ordered = true;
+    }
+    
+    public Collection<PVariable> getToVariables() {
+        return toVariables;
+    }
+    public boolean isOrdered() {                
+        return ordered;
+    }
+    
+    @Override
+    public Set<? extends PConstraint> getDeltaConstraints() {
+        return Collections.emptySet();
+    }
+    @Override
+    public int numParentSubPlans() {
+        return 1;
+    }
+    @Override
+    public void checkConsistency(SubPlan subPlan) {
+        super.checkConsistency(subPlan);
+        final SubPlan parentPlan = subPlan.getParentPlans().get(0);
+        
+        Preconditions.checkArgument(parentPlan.getVisibleVariables().containsAll(toVariables), 
+                () -> toVariables.stream()
+                        .filter(input -> !parentPlan.getVisibleVariables().contains(input)).map(PVariable::getName)
+                        .collect(Collectors.joining(",", "Variables missing from project: ", "")));
+    }
+
+    @Override
+    public String getShortName() {
+        return String.format("PROJECT%s_{%s}", ordered? "!" : "", 
+                toVariables.stream().map(PVariable::getName).collect(Collectors.joining(",")));
+    }
+    
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + (ordered ? 1231 : 1237);
+        result = prime * result
+                + ((toVariables == null) ? 0 : toVariables.hashCode());
+        return result;
+    }
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (!(obj instanceof PProject))
+            return false;
+        PProject other = (PProject) obj;
+        if (ordered != other.ordered)
+            return false;
+        if (toVariables == null) {
+            if (other.toVariables != null)
+                return false;
+        } else if (!toVariables.equals(other.toVariables))
+            return false;
+        return true;
+    }
+
+
+    
+
+}