Pools.java

package org.nutz.filepool;

import java.io.File;

/**
 * 文件池的一些帮助函数
 * 
 * @author zozoh(zozohtnt@gmail.com)
 */
public class Pools {

    public static File getFileById(File home, long id, String suffix) {
        return new File(getFilePathById(home, id, suffix));
    }

    public static String getFilePathById(File home, long id, String suffix) {
        StringBuilder sb = new StringBuilder(home.getAbsolutePath());
        sb.append(String.format("%016X", id).replaceAll("\\p{XDigit}{2}", "/$0"));
        if (null != suffix)
            sb.append(suffix);
        return sb.toString();
    }

    public static long getFileId(File home, File f) {
        String path = f.getAbsolutePath();
        int pos = -1;
        if(f.getName().indexOf('.') > -1)
            pos = path.lastIndexOf('.');
        String s = pos > 0    ? path.substring(home.getAbsolutePath().length(), pos)
                            : path.substring(home.getAbsolutePath().length());
        return Long.parseLong(s.replaceAll("[\\\\/]", ""), 16);
    }

}