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dataflow-shaded is a dataflow framework based on the javac compiler. It differs from the org.checkerframework:dataflow artifact in two ways. First, the packages in this artifact have been renamed to org.checkerframework.shaded.*. Second, unlike the dataflow artifact, this artifact contains the dependencies it requires.

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package org.checkerframework.dataflow.cfg.node;

import com.sun.source.tree.IdentifierTree;
import com.sun.source.tree.MemberSelectTree;
import com.sun.source.tree.Tree;

import org.checkerframework.checker.nullness.qual.Nullable;
import org.checkerframework.dataflow.qual.SideEffectFree;
import org.checkerframework.javacutil.BugInCF;
import org.checkerframework.javacutil.ElementUtils;
import org.checkerframework.javacutil.TreeUtils;

import java.util.Collection;
import java.util.Collections;
import java.util.Objects;

import javax.lang.model.element.VariableElement;

/**
 * A node for a field access, including a method accesses:
 *
 *  *   expression . field
 * 
 */
public class FieldAccessNode extends Node {
    /** The tree of the field access. */
    protected final Tree tree;

    /** The element of the accessed field. */
    protected final VariableElement element;

    /** The name of the accessed field. */
    protected final String field;

    /** The receiver node of the field access. */
    protected final Node receiver;

    /**
     * Creates a new FieldAccessNode.
     *
     * @param tree the tree from which to create a FieldAccessNode
     * @param receiver the receiver for the resulting FieldAccessNode
     */
    public FieldAccessNode(Tree tree, Node receiver) {
        super(TreeUtils.typeOf(tree));
        assert TreeUtils.isFieldAccess(tree);
        this.tree = tree;
        this.receiver = receiver;
        this.field = TreeUtils.getFieldName(tree);

        if (tree instanceof MemberSelectTree) {
            MemberSelectTree mstree = (MemberSelectTree) tree;
            assert TreeUtils.isUseOfElement(mstree) : "@AssumeAssertion(nullness): tree kind";
            this.element = TreeUtils.variableElementFromUse(mstree);
        } else if (tree instanceof IdentifierTree) {
            IdentifierTree itree = (IdentifierTree) tree;
            assert TreeUtils.isUseOfElement(itree) : "@AssumeAssertion(nullness): tree kind";
            this.element = TreeUtils.variableElementFromUse(itree);
        } else {
            throw new BugInCF("unexpected tree %s [%s]", tree, tree.getClass());
        }
    }

    public FieldAccessNode(Tree tree, VariableElement element, Node receiver) {
        super(element.asType());
        this.tree = tree;
        this.element = element;
        this.receiver = receiver;
        this.field = element.getSimpleName().toString();
    }

    public VariableElement getElement() {
        return element;
    }

    public Node getReceiver() {
        return receiver;
    }

    public String getFieldName() {
        return field;
    }

    @Override
    public Tree getTree() {
        return tree;
    }

    @Override
    public  R accept(NodeVisitor visitor, P p) {
        return visitor.visitFieldAccess(this, p);
    }

    @Override
    public String toString() {
        return getReceiver() + "." + field;
    }

    /**
     * Determine whether the field is static or not.
     *
     * @return whether the field is static or not
     */
    public boolean isStatic() {
        return ElementUtils.isStatic(getElement());
    }

    @Override
    public boolean equals(@Nullable Object obj) {
        if (!(obj instanceof FieldAccessNode)) {
            return false;
        }
        FieldAccessNode other = (FieldAccessNode) obj;
        return getReceiver().equals(other.getReceiver())
                && getFieldName().equals(other.getFieldName());
    }

    @Override
    public int hashCode() {
        return Objects.hash(getReceiver(), getFieldName());
    }

    @Override
    @SideEffectFree
    public Collection getOperands() {
        return Collections.singletonList(receiver);
    }
}