cdc.applic.expressions.ast.AbstractBinaryNode Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of cdc-applic-expressions Show documentation
Applicabilities Expressions.
The newest version!
package cdc.applic.expressions.ast;

import java.io.PrintStream;
import java.util.Objects;

import cdc.applic.expressions.Formatting;
import cdc.util.debug.Printables;
import cdc.util.lang.Checks;

/**
 * Base class of binary nodes.
 *
 * @author Damien Carbonne
 */
public abstract class AbstractBinaryNode extends AbstractOperatorNode {
    private final Node alpha;
    private final Node beta;
    private int hash = 0;

    protected AbstractBinaryNode(Node alpha,
                                 Node beta) {
        Checks.isNotNull(alpha, "alpha");
        Checks.isNotNull(beta, "beta");
        this.alpha = alpha;
        this.beta = beta;
    }

    public final Node getAlpha() {
        return alpha;
    }

    public final Node getBeta() {
        return beta;
    }

    @Override
    public final int getChildrenCount() {
        return 2;
    }

    @Override
    public final Node getChildAt(int index) {
        if (index == 0) {
            return alpha;
        } else if (index == 1) {
            return beta;
        } else {
            throw new IllegalArgumentException("Invalid index (" + index + ")");
        }
    }

    public abstract AbstractBinaryNode create(Node alpha,
                                              Node beta);

    @Override
    public final int getHeight() {
        return 1 + Math.max(alpha.getHeight(), beta.getHeight());
    }

    @Override
    public final void buildInfix(Formatting formatting,
                                 StringBuilder builder) {
        final boolean alphaParen = needParentheses(getAlpha());
        final boolean betaParen = needParentheses(getBeta());

        NodeKerning.addOpenParenthese(builder, alphaParen);
        getAlpha().buildInfix(formatting, builder);
        NodeKerning.addCloseParenthese(builder, alphaParen);
        getKerning().addSpace(builder, formatting, alphaParen);
        getKerning().addSymbol(builder, formatting);
        getKerning().addSpace(builder, formatting, betaParen);

        NodeKerning.addOpenParenthese(builder, betaParen);
        getBeta().buildInfix(formatting, builder);
        NodeKerning.addCloseParenthese(builder, betaParen);
    }

    @Override
    public  R accept(Visitor visitor) {
        return visitor.visitBinary(this);
    }

    @Override
    public final void print(PrintStream out,
                            int level) {
        Printables.indent(out, level);
        out.println(getKind());
        getAlpha().print(out, level + 1);
        getBeta().print(out, level + 1);
    }

    @Override
    public final boolean equals(Object object) {
        if (this == object) {
            return true;
        }
        if (object == null || !getClass().equals(object.getClass())) {
            return false;
        }
        final AbstractBinaryNode other = (AbstractBinaryNode) object;
        return getAlpha().equals(other.getAlpha())
                && getBeta().equals(other.getBeta());
    }

    @Override
    public final int hashCode() {
        if (hash == 0) {
            hash = Objects.hash(alpha, beta);
        }
        return hash;
    }

    @Override
    public String toString() {
        return getKind() + "(" + getAlpha() + "," + getBeta() + ")";
    }
}