Guava: cache: Get total number of elements in the cache

Cache class provides 'size' method, it returns the approximate number of entries in this cache.

 

Example

long cacheSize = empCache.size();

 

Find the below working application.

 

Employee.java

package com.sample.app.cache.model;

public class Employee {
	private Integer id;
	private String firstName;
	private String lastName;

	public Employee(Integer id, String firstName, String lastName) {
		super();
		this.id = id;
		this.firstName = firstName;
		this.lastName = lastName;
	}

	public Integer getId() {
		return id;
	}

	public void setId(Integer id) {
		this.id = id;
	}

	public String getFirstName() {
		return firstName;
	}

	public void setFirstName(String firstName) {
		this.firstName = firstName;
	}

	public String getLastName() {
		return lastName;
	}

	public void setLastName(String lastName) {
		this.lastName = lastName;
	}

	@Override
	public String toString() {
		return "Employee [id=" + id + ", firstName=" + firstName + ", lastName=" + lastName + "]";
	}

}

 

HelloWorld.java

package com.sample.app.cache;

import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;

import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.sample.app.cache.model.Employee;

public class HelloWorld {

	public static void main(String args[]) throws InterruptedException, ExecutionException {

		Cache<Integer, Employee> empCache = CacheBuilder.newBuilder().maximumSize(500)
				.expireAfterWrite(60, TimeUnit.SECONDS).recordStats().build();

		empCache.put(1, new Employee(1, "Krishna", "Gurram"));
		empCache.put(2, new Employee(2, "Ramadevi", "Amara"));

		long cacheSize = empCache.size();
		System.out.println("Approximate number of entries in the cache are : " + cacheSize);
	}

}

 

Output

Approximate number of entries in the cache are : 2

 

 

 

  

Previous                                                    Next                                                    Home