Class ProxyGenerator

src/main/java/groovy/util/ProxyGenerator.java:51–481

Generates 'Proxy' objects which implement interfaces, maps of closures and/or extend classes/delegates.

 * extend classes/delegates.
 */
@SuppressWarnings({"rawtypes", "serial"})
public class ProxyGenerator {
    private static final Map<Object,Object> EMPTY_CLOSURE_MAP = Collections.emptyMap();

    static {
        // wrap the standard MetaClass with the delegate
        setMetaClass(GroovySystem.getMetaClassRegistry().getMetaClass(ProxyGenerator.class));
    }

    /** Shared proxy generator instance used by Groovy's coercion helpers. */
    public static final ProxyGenerator INSTANCE = new ProxyGenerator();

    /**
     * Caches proxy classes. When, for example, a call like: <code>map as MyClass</code>
     * is found, then a lookup is made into the cache to find if a suitable adapter
     * exists already. If so, it is reused instead of generating a new one.
     */
    private final Map<CacheKey, ProxyGeneratorAdapter> adapterCache;
    private static final int CACHE_SIZE = Integer.getInteger("groovy.adapter.cache.default.size", 64);
    private static final float LOAD_FACTOR = 0.75f;
    private static final int INIT_CAPACITY = (int) Math.ceil(CACHE_SIZE / LOAD_FACTOR) + 1;
    {
        adapterCache = new LinkedHashMap<>(INIT_CAPACITY, LOAD_FACTOR, true) {
            /** {@inheritDoc} */
            @Override
            protected boolean removeEldestEntry(Map.Entry<CacheKey, ProxyGeneratorAdapter> entry) {
                return size() > CACHE_SIZE;
            }
        };
    }

    private boolean debug;
    private boolean emptyMethods;
    private ClassLoader override;

    // private ProxyGenerator() {} // TODO: Should we make ProxyGenerator singleton?

    /**
     * Reports whether generated source is echoed for debugging.
     *
     * @return {@code true} when debug output is enabled
     */
    public boolean getDebug() {
        return debug;
    }

    /**
     * Instructs <code>ProxyGenerator</code> to dump generated Groovy
     * source code to standard output during construction. This is useful
     * for debugging purposes but should be turned off in production.
     *
     * @param debug true if you want generated source to be printed
     */
    public void setDebug(boolean debug) {
        this.debug = debug;
    }

    /**