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/*
 * Copyright (c) 2007 through 2024 David Berkman
 *
 * This file is part of the SmallMind Code Project.
 *
 * The SmallMind Code Project is free software, you can redistribute
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 *
 * 1) The terms of GNU Affero General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or (at
 * your option) any later version.
 *
 * ...or...
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 * 2) The terms of the Apache License, Version 2.0.
 *
 * The SmallMind Code Project is distributed in the hope that it will
 * be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License or Apache License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * and the Apache License along with the SmallMind Code Project. If not, see
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 *
 * Additional permission under the GNU Affero GPL version 3 section 7
 * ------------------------------------------------------------------
 * If you modify this Program, or any covered work, by linking or
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package org.smallmind.nutsnbolts.inject;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.smallmind.nutsnbolts.reflection.FieldAccessor;
import org.smallmind.nutsnbolts.reflection.FieldUtility;

@Aspect
public class LazyFieldAspect {

  @Around(value = "execution(@org.smallmind.nutsnbolts.inject.LazyField * * (..)) && @annotation(lazyField) && this(called)", argNames = "thisJoinPoint, lazyField, called")
  public Object aroundLazyMethod (ProceedingJoinPoint thisJoinPoint, LazyField lazyField, Object called)
    throws Throwable {

    FieldAccessor fieldAccessor;

    if ((fieldAccessor = FieldUtility.getFieldAccessor(called.getClass(), lazyField.value())) == null) {
      throw new LazyError("Missing field(%s) in type(%s) with @%s annotated method(%s)", lazyField.value(), called.getClass().getName(), LazyField.class.getSimpleName(), thisJoinPoint.getSignature().getName());
    } else {

      Object fieldValue;

      if ((fieldValue = fieldAccessor.get(called)) == null) {
        fieldAccessor.set(called, fieldValue = thisJoinPoint.proceed());
      }

      return fieldValue;
    }
  }
}