２段階目終わりました

em-oop/src/Shape.java

@@ -1,16 +1,15 @@
 
-public class Shape {
+public abstract class Shape {
 	private String name;
+
 	public Shape(String name) {
 		this.name = name;
 	}
-	
-	public double area() {
-		return 0.0;
-	}
+
+	public abstract double area();
+
 	public void showInfo() {
 		System.out.println(this.name + "の面積は" + this.area() + "です");
 	}
-	
-	
+
 }