未賦值的實例變量

1.Dog類

public class Dog {
	private int size;
	private String name;
public int getSize() {
		return size;
	}

	public void setSize(int size) {
		this.size = size;
	}

	public String getName() {
		return name;
	}

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

}

2.測試類

public class Test_1 {
public static void main(String[] args) {
	Dog d4 = new Dog();
	System.out.println(d4.getName());
	System.out.println(d4.getSize());
}
}

3.結果

null

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