KwCheng's blog

The form of FileWriter class is as below:

FileWriter(String fileName, boolean append)

HashTable can improve our search time when we need to find data.

There is a example for HashTable class in java :

import java.util.Hashtable;

在String類別中的 empty() method可以用來檢查讀到的字串是否為空白行.

Ex :

There is a file , native2ascii.exe , in jdk bin folder.

We can use this execution file to achieve our purpose.

http.nonProxyHosts (default: <none>) 

1.  a wildcard character (*) can be used for matching.

try

{

try

{

try 

{

import java.util.concurrent.TimeUnit;

Java is not like c programming language , it doesn't have the command system("pasue").

But we can use some method to implement the similar function.

We can use String.split method to split the string into tokens.

    String[] result = "this is a book".split("\\s");

     for (int x=0; x<result.length; x++)

    {

         System.out.println(result[x]);

    }

The result will be:

this

is

a

book

We also can use StringTokenizer class to achieve the result we want.

The StringTokenizer is defined as          StringTokenizer(String str, String delim)

code example:

StringTokenizer st = new StringTokenizer("this is a book" , " ");

 while (st.hasMoreTokens()) 

 {

          System.out.println(st.nextToken());

 }

ref:http://docs.oracle.com/javase/7/docs/api/java/util/StringTokenizer.html

try

{

try

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String inputStr = "ab1da";

Pattern pattern = Pattern.compile("[abc]+\\d[ad]+");

在java中 , 要進行字串regular expression比對主要有兩種方法 , 

一種是用String中的matches method.

在Java中 , System.out.print的輸出的default都是在螢幕上 , 

如果我們想要更改輸出位置到file的話 , 我們可以使用以下這個指令:

1.字串比對

2.字元的輸入

1.System.in

2.Scanner

不能免俗的,第一篇文章一定要來一個"Hello World!"

public class Hello