Zapouzdření objektu.

sample.java

class Person
{
	private String name;
	private Address address;
	private int age;
	public Person(String name, Address address, int age)
	{
		this.assertName(name);
		this.assertAddress(address, age);
		this.assertAge(age);
		this.name = name;
		this.address = address;
		this.age = age;
	}
	
	
	public void setName(String val) {
		this.assertName(val);
		this.name = val;
	}
	
	
	public void setAddress(Address val) {
		this.assertAddress(val, this.age); //Člověk mladší devatenácti nemůže měnit adresu
		this.address = val;
	}
	
	
	public void setAge(int val) {
		this.assertAge(val);
		this.age = val;
	}
	
	
	// další metody
}