ReferenceTest

ReferenceTest.java

import java.io.*;
import java.util.*;

public class ReferenceTest {
  public static class Base {
    public int value = 0;
  }

  public static class Wrapper {
    private Base base;

    public Wrapper(Base base) {
      this.base = base;
    }

    public void update(int value) {
      base.value = value;
    }
  }

  public static void main(String[] args) {
    Base base = new Base();
    Wrapper wrapper = new Wrapper(base);
    wrapper.update(10);
    System.out.println("base> " + base.value);
  }
}