Constraint.java

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package org.apache.doris.nereids.trees.plans.commands;

import org.apache.doris.catalog.constraint.Constraint.ConstraintType;
import org.apache.doris.nereids.trees.expressions.Slot;
import org.apache.doris.nereids.trees.plans.logical.LogicalPlan;
import org.apache.doris.nereids.trees.plans.logical.LogicalProject;

import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;

import java.util.Objects;
import javax.annotation.Nullable;

/**
 * Constraint
 */
public class Constraint {
    private final ImmutableList<Slot> slots;
    private final LogicalPlan curTable;
    private final @Nullable LogicalPlan referenceTable;
    private final @Nullable ImmutableList<Slot> referenceSlots;
    private final ConstraintType type;

    Constraint(ConstraintType type, LogicalPlan curTable, ImmutableList<Slot> slots) {
        Preconditions.checkArgument(slots != null && !slots.isEmpty(),
                "slots of constraint can't be null or empty");
        this.type = type;
        this.slots = slots;
        this.curTable = Objects.requireNonNull(curTable,
                "table of constraint can't be null");
        this.referenceTable = null;
        this.referenceSlots = null;
    }

    Constraint(LogicalPlan curTable, ImmutableList<Slot> slots,
            LogicalPlan referenceTable, ImmutableList<Slot> referenceSlotSet) {
        Preconditions.checkArgument(slots != null && !slots.isEmpty(),
                "slots of constraint can't be null or empty");
        this.type = ConstraintType.FOREIGN_KEY;
        this.slots = slots;
        this.curTable = Objects.requireNonNull(curTable,
                "table of constraint can't be null");
        this.referenceTable = Objects.requireNonNull(referenceTable,
                "reference table in foreign key can not be null");
        this.referenceSlots = Objects.requireNonNull(referenceSlotSet,
                "reference slots in foreign key can not be null");
        Preconditions.checkArgument(referenceSlots.size() == slots.size(),
                "Foreign key's size must be same as the size of reference slots");
    }

    public static Constraint newUniqueConstraint(LogicalPlan curTable, ImmutableList<Slot> slotSet) {
        return new Constraint(ConstraintType.UNIQUE, curTable, slotSet);
    }

    public static Constraint newPrimaryKeyConstraint(LogicalPlan curTable, ImmutableList<Slot> slotSet) {
        return new Constraint(ConstraintType.PRIMARY_KEY, curTable, slotSet);
    }

    public static Constraint newForeignKeyConstraint(
            LogicalPlan curTable, ImmutableList<Slot> slotSet,
            LogicalPlan referenceTable, ImmutableList<Slot> referenceSlotSet) {
        return new Constraint(curTable, slotSet, referenceTable, referenceSlotSet);
    }

    public boolean isForeignKey() {
        return type == ConstraintType.FOREIGN_KEY;
    }

    public boolean isUnique() {
        return type == ConstraintType.UNIQUE;
    }

    public boolean isPrimaryKey() {
        return type == ConstraintType.PRIMARY_KEY;
    }

    public LogicalPlan toProject() {
        return new LogicalProject<>(ImmutableList.copyOf(slots), curTable);
    }

    public LogicalPlan toReferenceProject() {
        Preconditions.checkArgument(referenceSlots != null, "Reference slot set of foreign key cannot be null");
        return new LogicalProject<>(ImmutableList.copyOf(referenceSlots), referenceTable);
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("Constraint Type: ").append(type).append("\n");
        sb.append("Slot Set: ").append(slots).append("\n");
        sb.append("Current Table: ").append(curTable).append("\n");
        if (type.equals(ConstraintType.FOREIGN_KEY)) {
            sb.append("Reference Table: ").append(referenceTable).append("\n");
            sb.append("Reference Slot Set: ").append(referenceSlots);
        }
        return sb.toString();
    }
}