3.txt

一些面试题集 供大家参考 希望大家找到合适的工作

                   return null; 



           StringTokenizer commaToker =  new StringTokenizer(source,","); 



           String[] result = new String[commaToker.countTokens()]; 



           int i=0; 



           while(commaToker.hasMoreTokens()){ 



                   result[i] = commaToker.nextToken(); 



                   i++; 



           } 



           return result; 



  } 



循环遍历String数组 



Integer.parseInt(String s)变成int类型 



组成int数组 



Arrays.sort(int[] a), 



a数组升序 



降序可以从尾部开始输出 






2．金额转换，阿拉伯数字的金额转换成中国传统的形式如： 



（￥1011）－>（一千零一拾一元整）输出。 



3、继承时候类的执行顺序问题,一般都是选择题,问你将会打印出什么? 



答:父类： 



package test; 



public class FatherClass 



{ 



public FatherClass() 



{ 



System.out.println("FatherClass Create"); 



} 



} 



子类: 



package test; 



import test.FatherClass; 



public class ChildClass extends FatherClass 



{ 



public ChildClass() 



{ 



System.out.println("ChildClass Create"); 



} 



public static void main(String[] args) 



{ 



FatherClass fc = new FatherClass(); 



ChildClass cc = new ChildClass(); 



} 



} 



输出结果： 



C:>java test.ChildClass 



FatherClass Create 



FatherClass Create 



ChildClass Create 






4、内部类的实现方式? 



答：示例代码如下： 



package test; 



public class OuterClass 



{ 



private class InterClass 



{ 



public InterClass() 



{ 



System.out.println("InterClass Create"); 



} 



} 



public OuterClass() 



{ 



InterClass ic = new InterClass(); 



System.out.println("OuterClass Create"); 



} 



public static void main(String[] args) 



{ 



OuterClass oc = new OuterClass(); 



} 



} 



输出结果: 



C:>java test/OuterClass 



InterClass Create 



OuterClass Create 



再一个例题： 



public class OuterClass { 



private double d1 = 1.0; 



//insert code here 



} 



You need to insert an inner class declaration at line 3. Which two inner class declarations are 






valid?(Choose two.) 



A. class InnerOne{ 



public static double methoda() {return d1;} 



} 



B. public class InnerOne{ 



static double methoda() {return d1;} 



} 



C. private class InnerOne{ 



double methoda() {return d1;} 



} 



D. static class InnerOne{ 



protected double methoda() {return d1;} 



} 



E. abstract class InnerOne{ 



public abstract double methoda(); 



} 



说明如下： 



一.静态内部类可以有静态成员，而非静态内部类则不能有静态成员。 故 A、B 错 



二.静态内部类的非静态成员可以访问外部类的静态变量，而不可访问外部类的非静态变量；return d1 出错。 






故 D 错 



三.非静态内部类的非静态成员可以访问外部类的非静态变量。 故 C 正确 



四.答案为C、E 









5、Java 的通信编程，编程题(或问答)，用JAVA SOCKET编程，读服务器几个字符，再写入本地显示？ 



答:Server端程序: 



package test; 



import java.net.*; 



import java.io.*; 



public class Server 



{ 



private ServerSocket ss; 



private Socket socket; 



private BufferedReader in; 



private PrintWriter out; 



public Server() 



{ 



try 



{ 



ss=new ServerSocket(10000); 



while(true) 



{ 



socket = ss.accept(); 



String RemoteIP = socket.getInetAddress().getHostAddress(); 



String RemotePort = ":"+socket.getLocalPort(); 



System.out.println("A client come in!IP:"+RemoteIP+RemotePort); 



in = new BufferedReader(new 






InputStreamReader(socket.getInputStream())); 



String line = in.readLine(); 



System.out.println("Cleint send is :" + line); 



out = new PrintWriter(socket.getOutputStream(),true); 



out.println("Your Message Received!"); 



out.close(); 



in.close(); 



socket.close(); 



} 



}catch (IOException e) 



{ 



out.println("wrong"); 



} 



} 



public static void main(String[] args) 



{ 



new Server(); 



} 



}; 



Client端程序: 



package test; 



import java.io.*; 



import java.net.*; 






public class Client 



{ 



Socket socket; 



BufferedReader in; 



PrintWriter out; 



public Client() 



{ 



try 



{ 



System.out.println("Try to Connect to 127.0.0.1:10000"); 



socket = new Socket("127.0.0.1",10000); 



System.out.println("The Server Connected!"); 



System.out.println("Please enter some Character:"); 



BufferedReader line = new BufferedReader(new 






InputStreamReader(System.in)); 



out = new PrintWriter(socket.getOutputStream(),true); 



out.println(line.readLine()); 



in = new BufferedReader(new InputStreamReader(socket.getInputStream())); 



System.out.println(in.readLine()); 



out.close(); 



in.close(); 



socket.close(); 



}catch(IOException e) 



{ 



out.println("Wrong"); 



} 



} 



public static void main(String[] args) 



{ 



new Client(); 



} 



}; 



6、用JAVA实现一种排序，JAVA类实现序列化的方法(二种)？ 如在COLLECTION框架中，实现比较要实现什么样的接口？ 



答:用插入法进行排序代码如下 



package test; 



import java.util.*; 



class InsertSort 



{ 



ArrayList al; 



public InsertSort(int num,int mod) 



{ 



al = new ArrayList(num); 



Random rand = new Random(); 



System.out.println("The ArrayList Sort Before:"); 



for (int i=0;i<num ;i++ ) 



{ 



al.add(new Integer(Math.abs(rand.nextInt()) % mod + 1)); 



System.out.println("al["+i+"]="+al.get(i)); 



} 



} 



public void SortIt() 



{ 



Integer tempInt; 



int MaxSize=1; 



for(int i=1;i<al.size();i++) 



{ 



tempInt = (Integer)al.remove(i); 



if(tempInt.intValue()>=((Integer)al.get(MaxSize-1)).intValue()) 



{ 



al.add(MaxSize,tempInt); 



MaxSize++; 



System.out.println(al.toString()); 



} else { 



for (int j=0;j<MaxSize ;j++ ) 



{ 



if 






(((Integer)al.get(j)).intValue()>=tempInt.intValue()) 



{ 



al.add(j,tempInt); 



MaxSize++; 



System.out.println(al.toString()); 



break; 



}