Question

我试图弄清楚如何实现Apache Pool 2（我使用2.5）。作为初始POC，我使用firstName，lastName，employeeId和age（Observer Pattern）创建了一个Employee对象。我创建了一个实现PooledObjectFactory的EmployeeObjectFactory，在主类中我试图添加Employee类的对象。但是我得到了一个类转换异常（EmployeeObjects不能转换为PooledObjects）。那么我需要对EmployeeObjects进行哪些更改？

员工类

public class Employee{
 private String firstName;
 // omitting the getters and setters for other fields

 public static class Builder {
  private String firstName = "Unsub";
  // declared and initialized lastName, emailId and age 
  public Builder firstName(String val) {
   firstName = val;
   return this;
  }
  // Similarly for other values
  public EmployeeObject build() {
   return new EmployeeObject(this);
  }
}

 private EmployeeObject(Builder builder) {
  firstName = builder.firstName;
  // omitting rest of the code
 }
}

在EmployeeObjectFactory

中

public class EmployeeObjectFactory implements PooledObjectFactory<EmployeeObject> {

 @Override
 public PooledObject<EmployeeObject> makeObject() {
  return (PooledObject<EmployeeObject>) new EmployeeObject.Builder().build(); // This is where I'm getting the class cast
 }
 // Omitting rest of the code
}

主类

public static void main(String arg[]) throws Exception {
GenericObjectPool employeeObjectPool = new GenericObjectPool(new EmployeeObjectFactory());
employeeObjectPool.addObject();

我试图添加尽可能少的代码，因为即使我讨厌经历大量代码。任何帮助将不胜感激。

Answer 1

阅读完Apache Docs后，终于得到了答案。 DefaultPooledObject是我需要使用的。 DefaultPooledObject - “创建一个包装所提供对象的新实例，以便池可以跟踪池化对象的状态。”在makeObject（）函数中，我返回了一个DefaultPooledObject。所以我的代码看起来像

@Override
public PooledObject<EmployeeObject> makeObject() {
 return new DefaultPooledObject<>(new EmployeeObject.Builder().build());
}

将对象添加到Apache Pool时的类转换异常

1 个答案: