java正则表达式使用

package org.ankang06.admin;

import java.io.File;
import java.io.FileWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

public class CopyOfMainRun {

  public void test(){
    Pattern p=null; //正则表达式 

    Matcher m=null; //操作的字符串 

    boolean b; 

    String s=null; 

    StringBuffer sb=null; 

    int i=0; 

    //字符串匹配，这是不符合的 

     p = Pattern.compile("a*b"); //正则表达式表示首字母是a，中间是任意字符，结尾以b结束

     m = p.matcher("baaaaab"); 

     b = m.matches(); 

    System.out.println(b+"<br>;"); //输出：false

   //字符串匹配，这是符合的 

     p = Pattern.compile("a*b"); 

     m = p.matcher("aaaaab"); 

     b = m.matches(); 

     System.out.println(b+"<br>;"); //输出：ture

   //字符串替换 

     p = Pattern.compile("ab"); 

     m = p.matcher("aaaaab"); 

     s = m.replaceAll("d");    //找到字符串中所有的ad然后替换成d

     System.out.println(s+"<br>;"); //输出：aaaad
     
     

     p = Pattern.compile("a*b"); 

     m = p.matcher("aaaaab"); 

     s = m.replaceAll("d");   

     System.out.println(s+"<br>;"); //输出：d

     p = Pattern.compile("a*b"); 

     m = p.matcher("caaaaab"); 

     s = m.replaceAll("d");   

     System.out.println(s+"<br>;"); //输出：cd

   //字符串查找 

    p = Pattern.compile("cat"); 

    m = p.matcher("one cat two cats in the yard"); 

    sb = new StringBuffer(); 

    while (m.find()) { 

        m.appendReplacement(sb, "dog"); //找到与cat相同的字符用dog代替

        i++; 

    } 

    m.appendTail(sb); //将整个字符串中的cat替换成dog

    System.out.println(sb.toString()+"<br>;"); 

    System.out.println(i+"<br>;"); 

    i=0;  

    p = Pattern.compile("cat"); 

    m = p.matcher("one cat two ca tsi nthe yard"); 

     sb = new StringBuffer(); 

    while (m.find()) { 

        m.appendReplacement(sb, "dog"); 

        i++; 

    } 

    m.appendTail(sb); 

    System.out.println(sb.toString()+"<br>;"); 

    System.out.println(i+"<br>;"); 

     

     

    p = Pattern.compile("cat"); 

    m = p.matcher("one cat two cats in the yard"); 

    p=m.pattern(); 

    m = p.matcher("bacatab"); 

    b = m.matches(); 

    System.out.println(b+"<br>;");  

    s = m.replaceAll("dog");  

    System.out.println(s+"<br>;");  

     

    i=0; 

    p = Pattern.compile("(fds){2,}"); //匹配两个连续的fds

    m = p.matcher("dsa da fdsfds aaafdsafds aaf"); 

     sb = new StringBuffer(); 

    while (m.find()) { 

        m.appendReplacement(sb, "dog"); 

        i++; 

    } 

    m.appendTail(sb); 

    System.out.println(sb.toString()+"<br>;"); 

    System.out.println(i+"<br>;"); 

     

     p = Pattern.compile("cat"); 

     m = p.matcher("one cat two cats in the yard"); 

     sb = new StringBuffer(); 

     while (m.find()) { 

        m.appendReplacement(sb, "<font color=\"red\">;cat</font>;"); 

     } 

   m.appendTail(sb); 

   System.out.println(sb.toString()+"<br>;"); 

   String aa=sb.toString(); 

   System.out.println(aa+"<br>;"); 

   //字符串分割 

     p = Pattern.compile("a+"); //匹配连续的a字符串

     String[] a=p.split("caaaaaat"); //根据正则表达式将字符串分割

     for(i=0;i<a.length;i++) 

     { 

     System.out.println(a[i]+"<br>;");//输出：c和t 

     } 

     p = Pattern.compile("a+"); 

     a=p.split("c aa aaaa t",0); 

     for(i=0;i<a.length;i++) 

     { 

     System.out.println(a[i]+"<br>;");// 输出"c "," "," t". 

     } 

     p = Pattern.compile(" +"); 

     a=p.split("c aa    aaaa t",0); 

     for(i=0;i<a.length;i++) 

     { 

     System.out.println(a+"<br>;"); 

     } 

     p = Pattern.compile("\\+"); 

     a=p.split("dsafasdfdsafsda+dsagfasdfa+sdafds"); 

     System.out.println(a.length+"<br>;"); 

     for(i=0;i<a.length;i++) 

     { 

     System.out.println(a+"<br>;"); 

     } 

  }
  public static void main(String[] args) {
    Pattern p=null; //正则表达式 

    Matcher m=null; //操作的字符串 

    boolean b; 

    String s=null; 

    StringBuffer sb=null; 

    int i=0; 

    
    //字符串分割 
    

    p = Pattern.compile(" +"); 
    String[] a=p.split("caaaaaat"); 

    a=p.split("c aa    aaaa t",0); 

    for(i=0;i<a.length;i++) 

    { 

    System.out.println(a[i]+"<br>;"); 

    }


   
  }

}