1.编写java程序,输入三个整数,并求出三个整数的最大值和最小值。``
package com.lxh.sixteenchapter;
import java.util.Scanner;
public class InputUtil {
private InputUtil() {
}
private static final Scanner INPUT=new Scanner(System.in);
public static int getInt(String prompt) {
int num=0;
boolean flag=true;
while(flag) {
System.out.println(prompt); //打印提示信息
if(INPUT.hasNext()) {
flag=false;
num=INPUT.nextInt();
}else {
System.out.println("输入有误");
}
}
return num;
}
}
package com.lxh.sixteenchapter;
public interface INumberSerService {
public int [] stat(int count);
}
package com.lxh.sixteenchapter;
public class NumberServiceImpl implements INumberSerService {
@Override
public int[] stat(int count) {
int result[]=new int[2];
int data[]=new int[count];
for(int x=0;x<data.length;x++) {
data[x]=InputUtil.getInt("请输入第"+(x+1)+"数字");
}
result[0]=data[0]; //最大值
result[1]=data[0]; //最小值
for(int x=0;x<data.length;x++) {
if(data[x]>result[0]) {
result[0]=data[x];
}
if(data[x]<result[0]) {
result[1]=data[x];
}
}
return result;
}
}
package com.lxh.sixteenchapter;
public class Factory {
private static INumberSerService getInstance() {
return new NumberServiceImpl();
}
}
package com.lxh.sixteenchapter;
public class IOCaseDemo {
public static void main(String[] args) {
INumberService numberService = Factory.getInstance() ;
int result [] = numberService.stat(5) ;
System.out.println("最大值:" + result[0] + "、最小值:" + result[1]);
}
}
2、 从键盘输入文件的内容和要保存的文件名称,然后根据输入的名称创建文件,并将内容保存到文件中。
(1),定义一个文件操作类的服务接口
public interface IFileService {
public boolean save();
}
(2)在InputUtil类里面追加有输入字符串的处理方法
package com.lxh.sixteenchapter;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class InputUtil02 {
private static final BufferedReader INPUT=new BufferedReader(new InputStreamReader(System.in));
private InputUtil02() {}
public static String getString(String prompt) {
String str = null ;
boolean flag = true ;
while(flag) {
System.out.print(prompt);
try {
str = INPUT.readLine() ;
if (!"".equals(str)) {
flag = false ;
} else {
System.out.println("输入的内容不允许为空!");
}
} catch (IOException e) {
System.out.println("输入的内容不允许为空!");
}
}
return str ;
}
}
(3)定义文件操作的业务标准
import java.io.File;
public interface IFileServic02 {
public static final String SAVE_DIR ="E:"+File.separator+"File"+File.separator+"ll.txt";
public boolean save();
}
(4)定义实现子类
package com.lxh.sixteenchapter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintWriter;
public class FileServiceImpl02 implements IFileServic02 {
private String name;
private String count;
public FileServiceImpl02(String name, String count) {
this.name = InputUtil02.getString("请输入保存文件名称");
this.count = InputUtil02.getString("请输入保存文件内容");
}
@Override
public boolean save() {
File file=new File(IFileServic02.SAVE_DIR+this.name);
PrintWriter out=null;
try {
out=new PrintWriter(new FileOutputStream(file));
out.print(this.count);
} catch (FileNotFoundException e) {
return false;
}finally {
if(out!=null) {
out.close();
}
}
return true;
}
}
(5)建立工厂类
public class Factory02 {
public static IFileServic02 getInstance() {
return new FileServiceImpl02();
}
}
(6)测试
public class Test02 {
public static void main(String[] args) {
IFileServic02 test02=Factory02.getInstance();
System.out.println(test02.save());
}
}
执行结果
请输入保存文件名称1232564154841
请输入保存文件内容51651
true