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package org.jruby.runtime.opto;

import org.jruby.RubyModule;
import org.jruby.runtime.builtin.IRubyObject;

A tuple representing the data needed to verify a cached constant:
The value of the constant
The generation of the constant's invalidator at the time of caching
The constant's invalidator
(Optional) the hashcode of the module form which the constant was cache
/**
 * A tuple representing the data needed to verify a cached constant:
 * 
 * <li>The value of the constant</li>
 * <li>The generation of the constant's invalidator at the time of caching</li>
 * <li>The constant's invalidator</li>
 * <li>(Optional) the hashcode of the module form which the constant was cache</li>
 */
public class ConstantCache {
    public final IRubyObject value;
    public final Object generation;
    public final Invalidator invalidator;
    public final int id;

    
Construct a new ConstantCache with the given elements.
Params:
value – 
generation – 
invalidator – 
targetHash – /**
     * Construct a new ConstantCache with the given elements.
     * 
     * @param value
     * @param generation
     * @param invalidator
     * @param targetHash 
     */
    public ConstantCache(IRubyObject value, Object generation, Invalidator invalidator, int targetHash) {
        this.value = value;
        this.generation = generation;
        this.invalidator = invalidator;
        this.id = targetHash;
    }

    
Construct a new ConstantCache with the given elements.
Params:
value – 
generation – 
invalidator – /**
     * Construct a new ConstantCache with the given elements.
     * 
     * @param value
     * @param generation
     * @param invalidator 
     */
    public ConstantCache(IRubyObject value, Object generation, Invalidator invalidator) {
        this(value, generation, invalidator, -1);
    }

    
Check if the given ConstantCache is non-null and valid, given the target module.
This method is static to ensure it is inlinable as trivially as possible.
/**
     * Check if the given ConstantCache is non-null and valid, given the target module.
     * 
     * This method is static to ensure it is inlinable as trivially as possible.
     */
    public static boolean isCachedFrom(RubyModule target, ConstantCache cache) {
        return cache != null
                && cache.value != null
                && cache.generation == cache.invalidator.getData()
                && cache.id == target.id;
    }

    
Check if the given ConstantCache is non-null and valid.
This method is static to ensure it is inlinable as trivially as possible.
/**
     * Check if the given ConstantCache is non-null and valid.
     * 
     * This method is static to ensure it is inlinable as trivially as possible.
     */
    public static boolean isCached(ConstantCache cache) {
        return cache != null
                && cache.value != null
                && cache.generation == cache.invalidator.getData();
    }
}