controlflow.java

本代码以J2SE 5.0为开发环境

package book.basic;

public class ControlFlow {
	/** 目标数字 */
	public static int TARGET_NUMBER = 10;

	/**
	 * 通过if条件语句和递归方法将n的值逐步变成TARGET_NUMBER
	 */
	public void ifstatement(int n) {
		System.out.print(n + " ");
		if (n == TARGET_NUMBER) {
			System.out.println();
		} else if (n < TARGET_NUMBER) {
			this.ifstatement(++n);
		} else {
			this.ifstatement(--n);
		}
	}

	/**
	 * 通过for循环语句将n的值逐步变成TARGET_NUMBER
	 */
	public void forstatement(int n) {
		for (; n > TARGET_NUMBER; n--) {
			System.out.print(n + " ");
		}
		for (; n < TARGET_NUMBER; n++) {
			System.out.print(n + " ");
		}
		System.out.println(n);
	}

	/**
	 * 通过while循环语句将n的值逐步变成TARGET_NUMBER
	 */
	public void whilestatement(int n) {
		while (n > TARGET_NUMBER) {
			System.out.print(n-- + " ");
		}
		while (n < TARGET_NUMBER) {
			System.out.print(n++ + " ");
		}
		System.out.println(n);
	}

	/**
	 * 通过do...while循环语句将n的值逐步变成TARGET_NUMBER
	 */
	public void dowhilestatement(int n) {
		if (n > TARGET_NUMBER) {
			do {
				System.out.print(n-- + " ");
			} while (n > TARGET_NUMBER);
		} else if (n < TARGET_NUMBER) {
			do {
				System.out.print(n++ + " ");
			} while (n < TARGET_NUMBER);
		}
		System.out.println(n);
	}

	/**
	 * switch...case选择语句示例
	 */
	public void switchcasestatement(int n) {
		switch (n) {
		case 10:
			System.out.println("n = 10");
			break;
		case 9:
			System.out.println("n = 9");
			break;
		case 8:
			System.out.println("n = 8");
			break;
		default:
			System.out.println("n != 8且n!=9且n!=10");
			break;
		}
	}

	public static void main(String[] args) {
		ControlFlow test = new ControlFlow();
		int n = 0;
		System.out.println("ifstatement方法的输出：");
		test.ifstatement(n);
		System.out.println("forstatement方法的输出：");
		test.forstatement(n);
		System.out.println("whilestatement方法的输出：");
		test.whilestatement(n);
		System.out.println("dowhilestatement方法的输出：");
		test.dowhilestatement(n);
		System.out.println("switchcasestatement方法的输出：");
		test.switchcasestatement(n);
	}
//	ifstatement方法的输出：
//	0 1 2 3 4 5 6 7 8 9 10 
//	forstatement方法的输出：
//	0 1 2 3 4 5 6 7 8 9 10
//	whilestatement方法的输出：
//	0 1 2 3 4 5 6 7 8 9 10
//	dowhilestatement方法的输出：
//	0 1 2 3 4 5 6 7 8 9 10
//	switchcasestatement方法的输出：
//	n != 8, n!=9, n!=10
	
}