findingintegers.java

nanjing university cs 的java课件。 对新手很有用。付课件中源码。

import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.*;

class FindingIntegers{
	public static void main(String[] args){
		//String regEx = "[+|-]?(\\d+(\\.\\d*)?)|(\\.\\d+)";
		String regEx = "[+|-]?((\\d+(\\.\\d*)?)|(\\.\\d+))";
		String str = "256 is the square of 16 and -2.5 squared is 6.25 "
			+ "and -.243 is less than 0.12345.";
		char[] marker = new char[str.length()];
		Arrays.fill(marker, ' ');
		
		Pattern pattern = Pattern.compile(regEx);
		Matcher m = pattern.matcher(str);
		
		while(m.find()){
			System.out.println("Pattern found at Strart: " + m.start()
				+ " End: " + m.end());
			System.out.println(m.group());
			Arrays.fill(marker, m.start(), m.end(), '^');
		}
		
		System.out.println(str);
		System.out.println(new String(marker));
	}
}