SerializeControl.java

package com.avaje.ebean.bean;

/**
 * This is ONLY used for <b>subclassed</b> entity beans.
 * <p>
 * This is NOT USED for entity beans that are enhanced via a javaagent or ant
 * task etc. This is only used when the entity beans are created as a subclass
 * of the original class.
 * </p>
 * <p>
 * Allows the developer to control whether beans and collections are serialized
 * to plain 'vanilla' classes or left in byte code generated subclasses.
 * <p>
 * Vanilla beans are beans that have plain ordinary classes as opposed to
 * specially generated classes that Ebean creates. Ebean creates classes (using
 * ASM) to support lazy loading (reference beans) and concurrency checking etc.
 * </p>
 * <p>
 * SerializeControl gives you the ability to control whether an object graph is
 * serialized to plain 'vanilla' objects or in the special byte code generated
 * form. There are pros and cons for both approaches depending on whether you
 * want to support "FULL" concurrency checking and lazy loading when the object
 * graph is deserialized.
 * </p>
 * <p>
 * Note that BeanMap, BeanList and BeanSet are not byte code generated. They are
 * ordinary classes. However you may wish to have these serialized to the
 * underlying List Set and Map implementations for the benefit that they can be
 * deserialised in a JVM without <em>ANY</em> ebean code at all.
 * </p>
 */
public class SerializeControl {

  private static final String BEANS = "com.avaje.ebean.vanillabeans";

  private static final String COLLECTIONS = "com.avaje.ebean.vanillacollections";

  private static Boolean getDefault(String key, Boolean dflt) {
    String val = System.getProperty(key);
    if (val != null) {
      return val.equalsIgnoreCase("true");
    }
    return dflt;
  }

  private static ThreadLocal<Boolean> vanillaBeans = new ThreadLocal<Boolean>() {
    protected synchronized Boolean initialValue() {
      return getDefault(BEANS, Boolean.TRUE);
    }
  };

  private static ThreadLocal<Boolean> vanillaCollections = new ThreadLocal<Boolean>() {
    protected synchronized Boolean initialValue() {
      return getDefault(COLLECTIONS, Boolean.TRUE);
    }
  };

  /**
   * Set the JVM wide default for Beans.
   */
  public static void setDefaultForBeans(boolean vanillaOn) {
    Boolean b = Boolean.valueOf(vanillaOn);
    System.setProperty(BEANS, b.toString());
  }

  /**
   * Set the JVM wide default for Collections.
   */
  public static void setDefaultForCollections(boolean vanillaOn) {
    Boolean b = Boolean.valueOf(vanillaOn);
    System.setProperty(COLLECTIONS, b.toString());
  }

  /**
   * Reset the mode for beans and collections back to the JVM wide default
   * setting.
   */
  public static void resetToDefault() {
    Boolean beans = getDefault(BEANS, Boolean.FALSE);
    setVanillaBeans(beans);

    Boolean coll = getDefault(COLLECTIONS, Boolean.FALSE);
    setVanillaCollections(coll);
  }

  /**
   * Set the mode for both Beans and Collections.
   */
  public static void setVanilla(boolean vanillaOn) {
    if (vanillaOn) {
      vanillaBeans.set(Boolean.TRUE);
      vanillaCollections.set(Boolean.TRUE);
    } else {
      vanillaBeans.set(Boolean.FALSE);
      vanillaCollections.set(Boolean.FALSE);
    }
  }

  /**
   * Return true if beans are serialized to Vanilla as opposed to byte code
   * generated subclasses.
   */
  public static boolean isVanillaBeans() {
    return (Boolean) vanillaBeans.get();
  }

  /**
   * Set whether beans should be serialized to Vanilla as opposed to byte code
   * generated subclasses.
   */
  public static void setVanillaBeans(boolean vanillaOn) {
    vanillaBeans.set(vanillaOn);
  }

  /**
   * Return true if collections are serialized to be plain Lists Sets or Maps as
   * opposed to BeanList, BeanMap or BeanSet.
   */
  public static boolean isVanillaCollections() {
    return (Boolean) vanillaCollections.get();
  }

  /**
   * Set whether collections should be serialized to Vanilla Lists Sets or Maps
   * (instead of BeanList, BeanMap or BeanSet).
   */
  public static void setVanillaCollections(boolean vanillaOn) {
    vanillaCollections.set(vanillaOn);
  }
}