Add InjectBeanPostProcessor.java

Author: JcoderPaul

Spring_part_3/src/main/java/spring/oldboy/bean_post_processor/InjectBeanPostProcessor.java

@@ -0,0 +1,46 @@
+package spring.oldboy.bean_post_processor;
+
+/* Пример самописного пост-процессора с основным ...BeforeInitialization методом */
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.config.BeanPostProcessor;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+import org.springframework.stereotype.Component;
+import org.springframework.util.ReflectionUtils;
+
+import java.util.Arrays;
+
+@Component
+public class InjectBeanPostProcessor implements BeanPostProcessor, ApplicationContextAware {
+
+    private ApplicationContext applicationContext;
+
+    @Override
+    public Object postProcessBeforeInitialization(Object bean, String beanName)
+                                                                    throws BeansException {
+        Arrays.stream(bean.getClass().getDeclaredFields())
+                .filter(field -> field.isAnnotationPresent(InjectBean.class))
+                .forEach(field -> {
+                    Object beanToInject = applicationContext.getBean("pool2",field.getType());
+                    ReflectionUtils.makeAccessible(field);
+                    ReflectionUtils.setField(field, bean, beanToInject);
+                });
+
+        return bean;
+    }
+
+    @Override
+    public Object postProcessAfterInitialization(Object bean, String beanName)
+                                                                    throws BeansException {
+        return bean;
+    }
+
+    @Override
+    public void setApplicationContext(ApplicationContext applicationContext)
+                                                                    throws BeansException {
+        this.applicationContext = applicationContext;
+    }
+
+
+}