java计算文件大小

package com.shm.wechat.utils;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.nio.channels.FileChannel;

import com.shm.wechat.utils.Constant;

/**
 * 文件操作工具类
 *
 */
public class FileUtil {

    
    public static void main(String[] args) {  
        System.out.println(getFileSize("E:\tomcat.zip"));
    }  
    
    /**
     * 计算文件大小
     * @param  filePath
     * @return 单位是byte
     */
    public static long getFileSize(String filePath) {  
        long size = 0;
        FileInputStream fis= null;
        FileChannel fc= null;  
        try {  
            File f = new File(filePath);  
            if (f.exists() && f.isFile()){  
                fis= new FileInputStream(f);  
                fc= fis.getChannel();  
                size = fc.size();
            }else{  
                Constant.LOGGER.error("{}，file doesn't exist or is not a file", filePath);
            }  
        } catch (FileNotFoundException e) {  
            Constant.LOGGER.error("文件大小检查发生异常，{}", e.getMessage());
        } catch (IOException e) {  
            Constant.LOGGER.error("文件大小检查发生异常，{}", e.getMessage());
        } finally {  
            if (null!=fc){  
                try{  
                    fc.close();  
                }catch(IOException e){  
                    Constant.LOGGER.error("FileChannel资源关闭发生异常，{}", e.getMessage());
                }  
            }  
            if (null!=fis){  
                try{  
                    fis.close();  
                }catch(IOException e){  
                    Constant.LOGGER.error("FileInputStream资源关闭发生异常，{}", e.getMessage());
                }  
            }   
        }  
        return size;
    }  
    
    
}