utils.java

图书馆管理的源代码文件

package com.nitpro.utils;

import java.text.SimpleDateFormat;
import java.util.Date;

public class Utils {
    public static boolean isDateFmt(String str, String fmt){
    	boolean r = false;
    	try {
        	SimpleDateFormat sdf = new SimpleDateFormat(fmt);
			Date d = sdf.parse(str);
			r = true;
		} catch (Exception e) {
			//e.printStackTrace();
		}finally{
			return r;
		}
    }

    public static boolean isDoubleFmt(String str){
    	boolean r = false;
    	try {
			double d = Double.parseDouble(str);
			r = true;
		} catch (Exception e) {
			//e.printStackTrace();
		}finally{
			return r;
		}
    }

    public static boolean isIntegerFmt(String str){
    	boolean r = false;
    	try {
			int d = Integer.parseInt(str);
			r = true;
		} catch (Exception e) {
			//e.printStackTrace();
		}finally{
			return r;
		}
    }
    
    public static Date strToDate(String str, String fmt){
    	Date d = null;
    	if(!isDateFmt(str, fmt)){
    		return d;
    	}else{
        	try {
        	    SimpleDateFormat sdf = new SimpleDateFormat(fmt);
			    d = sdf.parse(str);
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    	}
	    return d;
    }

    public static String dateToStr(Date date, String fmt){
    	String str = "";
    	if(date == null){
    		return str;
    	}
        try {
            SimpleDateFormat sdf = new SimpleDateFormat(fmt);
            str = sdf.format(date);
    	} catch (Exception e) {
    		e.printStackTrace();
    	}
    	return str;
    }
    
    public static Double strToDouble(String str){
    	Double d = null;
    	if(!isDoubleFmt(str)){
    		return d;
    	}else{
        	try {
			    d = Double.parseDouble(str);
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    	}
	    return d;
    }
    
    public static Integer strToInteger(String str){
    	Integer d = null;
    	if(!isIntegerFmt(str)){
    		return d;
    	}else{
        	try {
			    d = Integer.parseInt(str);
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    	}
	    return d;
    }
}