package example;

public class Hello {
    public String mainHandler(KeyValueClass kv) {
        System.out.println("Hello world!");
        System.out.println(String.format("key1 = %s", kv.getKey1()));
        System.out.println(String.format("key2 = %s", kv.getKey2()));
        return String.format("Hello World");
    }
}

package example;
public class KeyValueClass {
    String key1;
    String key2;

    public String getKey1() {
        return this.key1;
    }   
    public void setKey1(String key1) {
        this.key1 = key1;
    }   
    public String getKey2() {
        return this.key2;
    }   
    public void setKey2(String key2) {
        this.key2 = key2;
    }   

    public KeyValueClass() {
    }   
}