Action 继承 ActionSupport

package exaction;

import com.opensymphony.xwork2.ActionSupport;

public class PrimeAction extends ActionSupport {
	
	//
	private static final long serialVersionUID = 1L;

	private int num;
	private String number;

	public String execute() {
		num = Integer.valueOf(number);
		if (!IsPrimeNumber(num)) {
			addFieldError("number", "You entered a non Prime");
			// 如果不是质数那么添加出错信息，并且返回
			pause(INPUT);
		}
		if (IsPrimeNumber(num))
			return SUCCESS;
		return INPUT;
	}

	public Boolean IsPrimeNumber(int i) {
		// 质数的判断函数
		int m = (int) Math.sqrt(i);
		for (int n = 2; n <= m; n++) {
			if (i % n == 0)
				return false;
		}
		return true;
	}

	public String getNumber() {
		return number;
	}

	public void setNumber(String number) {
		this.number = number;
	}
}

代码来自精通struts2 第三章