Test Redundant Object Pool : Object Pool « Apache Common « Java

1. Java
2. Apache Common
3. Object Pool

Test Redundant Object Pool

import java.util.HashMap;

import org.apache.commons.pool.impl.SoftReferenceObjectPool;

public class TestRedundantObjectPool {


  public static void main(String args[]) throws Exception {

    SoftReferenceObjectPool pool =
      new SoftReferenceObjectPool(new EmployeeFactory(), 5);

    try{

      System.err.println("Number of employees in pool: " + pool.getNumIdle());

      Employee employee = (Employee)pool.borrowObject();

      System.err.println("Borrowed Employee: " + employee);

      employee.doWork();

      pool.returnObject(employee);

      // employee = null;

      HashMap map = new HashMap();

      System.err.println("Running memory intensive operation");
      for(int i = 0; i < 1000000; i++) {
        map.put(new Integer(i), new String("Fred Flintstone" + i));
      }

    }catch(OutOfMemoryError e) {
      System.err.println("Borrowed employee after OutOfMemory: " +
        pool.borrowObject());
      System.err.println("Error: "  + e);
    }
  }
}

----------------------------

import org.apache.commons.pool.BaseKeyedPoolableObjectFactory;

public class SkilledEmployeeFactory extends BaseKeyedPoolableObjectFactory {

  public Object makeObject(Object key) {
    if(key == null || !(key instanceof String) || ((String)key).length() == 0)
      throw new IllegalArgumentException("Invalid key specified");
    return new SkilledEmployee(key.toString());
  }

  /*public boolean validateObject(Object key, Object obj) {
    if(obj instanceof Employee) {
      if(((Employee)obj).getName() == null)
        return true;
    }
    return false;
  }

  public void passivateObject(Object obj) throws Exception {
    if(obj instanceof Employee) {
      ((Employee)obj).setName(null);
    } else throw new Exception("Unknown object");
  }*/
}

---------------------------------

public class SkilledEmployee extends Employee {

  private String skill;

  public SkilledEmployee(String skill) {
    this.skill = skill;
  }

  public String getSkill() {
    return this.skill;
  }

  public String toString() {
    return getSkill() + " -- " + getName();
  }
}

---------------------------------------
import org.apache.commons.pool.BasePoolableObjectFactory;

public class EmployeeFactory extends BasePoolableObjectFactory {

  public Object makeObject() {
    return new Employee();
  }

  public boolean validateObject(Object obj) {
    if(obj instanceof Employee) {
      if(((Employee)obj).getName() == null)
        return true;
    }
    return false;
  }

  public void passivateObject(Object obj) throws Exception {
    if(obj instanceof Employee) {
      ((Employee)obj).setName(null);
    } else throw new Exception("Unknown object");
  }
}

--------------------------------

public class Employee {

  private static int base = 0;


  private int id;

  private String name;

  public Employee() {
    this.id = base++;
  }

  public int getId() {
    return this.id;
  }

  public String getName() {
    return this.name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public void doWork() {
    // does nothing
  }

  public String toString() {
    return ("Id: " + this.id + ", Name: " + this.name);
  }

  public void finalize() {
    System.err.println("Employee " + toString() + " made redundant");
  }
}
           
       

TestRedundantObjectPool.zip( 1,219 k)

Related examples in the same category

1.	Keyed Object Pool
2.	Test Object Pool
3.	Soft Reference Object Pool Demo