使用IntelljIDEA生成接口的类继承图及装饰器模式

类图生成方法###

以一个装饰器模式实现数学运算的例子为例。

1. 安装 Intellj Ultimate ， lience server: http://xdouble.cn:8888/

2. 在类上右键点击 class diagram :
   

3. 在得到的类的框框上 “双指单击”或右键 ， 选择 show Implementations :
   

4. 得到的实现类列表上， Ctrl + A 全选
   

5. Enter 得到类图结果，上面有 导出图片功能。
   

6. 可以查看接口及实现类的覆写方法
   

7. 调整布局
   

8. 添加额外的类
   如果发现还有点单独的接口有关联但是不在上述继承体系里, 可以添加额外的 class diagram 并按上如法炮制。

9. 导出图片保存

装饰器代码###

Function.java 函数接口, sources 是被装饰的内层函数运算。

package zzz.study.patterns.decorator.func;

public abstract class Function {
	
	protected Function[] sources;
	
	public Function(Function[] sources) {
		this.sources = sources;
	}
	
	public Function(Function f) {
		this(new Function[] {f});
	}

	public abstract double f(double t);
	
	public String toString() {
		String name = this.getClass().toString();
		StringBuffer buf = new StringBuffer(name);
		if (sources.length > 0) {
			buf.append('(');
			for (int i=0; i < sources.length; i++) {
				if (i > 0)
					buf.append(",");
				buf.append(sources[i]);
			}
			buf.append(')');
		}
		return buf.toString();
	}
}

Constant.java ：常量函数

package zzz.study.patterns.decorator.func;

public class Constant extends Function {
	
	private double constant;
	
	public Constant() {
		super(new Function[] {});
	}
	
	public Constant(double constant) {
		super(new Function[]{});
		this.constant = constant;
	}
	
	public double f(double t) {
		return constant;
	}
	
	public String toString() {
		return Double.toString(constant);
	}

}

T.java : 线性函数

package zzz.study.patterns.decorator.func;

public class T extends Function {

	public T() {
		super(new Function[] {});
	}
	
	public double f(double t) {
		return t;
	}
	
	public String toString() {
		return "t";
	}
	
}

Square.java ：平方函数

package zzz.study.patterns.decorator.func;

public class Square extends Function {
	
	public Square() {
		super(new Function[] {});
	}
	
	public Square(Function f) {
		super(new Function[] {f});
	}
	
	public double f(double t) {
		return Math.pow(sources[0].f(t),2);
	}
	
    public String toString() {
		
		StringBuffer buf = new StringBuffer("");
		if (sources.length > 0) {
			buf.append('(');
			buf.append(sources[0]);
			buf.append('^');
			buf.append(2);
			buf.append(')');
		}
		return buf.toString();
	}
    
}

ExpDouble.java ：指数函数

package zzz.study.patterns.decorator.func;

public class ExpDouble extends Function {
	
	private double  expDouble;  // 指数的底数
	
	public ExpDouble() {
		super(new Function[] {});
	}
	
	public ExpDouble(double expDouble, Function f) {
		super(new Function[] {f});
		this.expDouble = expDouble;
	}	
	
	public double f(double t) {
		return Math.pow(expDouble, sources[0].f(t));
	}
	
    public String toString() {
		
		StringBuffer buf = new StringBuffer("");
		if (sources.length > 0) {
			buf.append('(');
			buf.append('(');
			buf.append(expDouble);
			buf.append(')');
			buf.append('^');
			buf.append(sources[0]);
			buf.append(')');
		}
		return buf.toString();
	}
  

}

Pow.java ：幂函数

package zzz.study.patterns.decorator.func;

public class Pow extends Function {
	
	private double  pow;  // 幂函数的指数
	
	public Pow() {
		super(new Function[] {});
	}
	
	public Pow(Function f, double pow) {
		super(new Function[] {f});
		this.pow = pow;
	}	
	
	public double f(double t) {
		return Math.pow(sources[0].f(t), pow);
	}
	
    public String toString() {
		
		StringBuffer buf = new StringBuffer("");
		if (sources.length > 0) {
			buf.append('(');
			buf.append(sources[0]);
			buf.append('^');
			buf.append('(');
			buf.append(pow);
			buf.append(')');
			buf.append(')');
		}
		return buf.toString();
	}  
}

Arithmetic.java ：四则运算

package zzz.study.patterns.decorator.func;

public class Arithmetic extends  Function {
	
	protected char op;
	
	public Arithmetic(char op, Function f1, Function f2) {
		super(new Function[] {f1, f2});
		this.op = op;
	}
	
	public double f(double t) {
		switch(op) {
			case '+':
				return sources[0].f(t) + sources[1].f(t);
			case '-':
				return sources[0].f(t) - sources[1].f(t);
			case '*':
				return sources[0].f(t) * sources[1].f(t);
			case '/':
				return sources[0].f(t) / sources[1].f(t);
			default:
				return 0;
		}
	}
	
	public String toString() {
		
		StringBuffer buf = new StringBuffer("");
		if (sources.length > 0) {
			buf.append('(');
			buf.append(sources[0]);
			buf.append(Character.toString(op));
			buf.append(sources[1]);
			buf.append(')');
		}
		return buf.toString();

	}

}

Sin.java , Cos.java 请读者自行完成。

测试：

package zzz.study.patterns.decorator;

import zzz.study.patterns.decorator.func.Arithmetic;
import zzz.study.patterns.decorator.func.Cos;
import zzz.study.patterns.decorator.func.Function;
import zzz.study.patterns.decorator.func.Sin;
import zzz.study.patterns.decorator.func.Square;
import zzz.study.patterns.decorator.func.T;

public class ShowFunction {
	
	public static void main(String[] args) {
		Function complexFunc = new Arithmetic('+', new Square(new Sin(new T())), new Square(new Cos(new T())));
		System.out.println(complexFunc + " = " + complexFunc.f(100.0));
		
	}
}

在 《Java函数接口实现函数组合及装饰器模式》 一文中，使用 Function 接口有更简洁的装饰器模式实现。