范型练习

创建一个范型的类：Pattern.java

public class Pattern<T,K,M> {
    T cat;
    K dog;
    M pig;
    public Pattern() {
        this.cat=null;
        this.dog=null;
        this.pig=null;
    }
    public Pattern(T cat,K dog,M pig) {
        this.cat=cat;
        this.dog=dog;
        this.pig=pig;
    }
    public String toString() {
        return "Cat: "+cat.toString()+" Dog: "+dog.toString()+" Pig: "+pig.toString();
    }
}

测试这个范型类：PatternTest.java

public class PatternTest {
    public static void main(String args[]) {
        Pattern<String,Integer,Integer> s=new Pattern<String,Integer,Integer>();
        s.cat="I am a CatString";
        s.dog=555;
        s.pig=999;
        System.out.println(s);
    }
}

运行结果：

[Jack@win 范型]$ javac PatternTest.java
[Jack@win 范型]$ java PatternTest
Cat: I am a CatString Dog: 555 Pig: 999