java 文件处理

Java代码

package javax.org.path;
import java.math.BigDecimal;
/**
 * @Author:jilongliang
 * @Date :2013-6-18
 * @Project:JTool
 * @Class:AccessFile.java
 * @Description:文件处理类
 */
public class AccessFile {
    public static final long KB = 1024;//KB
    public static final long MB = KB * KB;//MB
    public static final long GB = KB * MB;//GB
    /**
     * 处理文件大小
     */
    public static String fileSize(long file) {
        if (file <= 0) {
            return "";
        } else if (file < MB) {
            BigDecimal b = new BigDecimal((double) file / KB);
            return b.setScale(2, BigDecimal.ROUND_HALF_UP).doubleValue() + "K";
        } else if (file < GB) {
            BigDecimal b = new BigDecimal((double) file / MB);
            return b.setScale(2, BigDecimal.ROUND_HALF_UP).doubleValue() + "M";
        } else {
            BigDecimal b = new BigDecimal((double) file / GB);
            return b.setScale(2, BigDecimal.ROUND_HALF_UP).doubleValue() + "G";
        }
    }
    /**获取当前工程路径
     * @return
     */
    public static String getSysPath() {
        //String path = Thread.currentThread().getContextClassLoader().getResource("").toString();
        String path = Thread.currentThread().getContextClassLoader().getResource(".").toString();
        String temp = path.replaceFirst("file:/", "").replaceFirst("WEB-INF/classes/", "");
        String separator = System.getProperty("file.separator");
        String resultPath = temp.replaceAll("/", separator + separator);
        return resultPath;
    }
    /**
     * Thread.currentThread().getContextClassLoader().getResource("")
     * 的getResource里面空串或者点或者是/输出的路径是一致
     * "" D:Eclipse3.7JTooluildclasses
     * .  D:Eclipse3.7JTooluildclasses
     * -/ D:Eclipse3.7JTooluildclasses
     * @return
     */
    public static String getClassPath() {
        //String path = Thread.currentThread().getContextClassLoader().getResource("").toString();
        //String path = Thread.currentThread().getContextClassLoader().getResource(".").toString();
        String path = Thread.currentThread().getContextClassLoader().getResource("/").toString();
        String temp = path.replaceFirst("file:/", "");
        String separator = System.getProperty("file.separator");
        String resultPath = temp.replaceAll("/", separator + separator);
        return resultPath;
    }
    /**
     * getClassLoader().getResource()方法参数空串和点都是输出相同的路径唯有/是报空指针
     * "" D:Eclipse3.7JTooluildclasses
     * .  D:Eclipse3.7JTooluildclasses
     *-/  报空指针
     * @return
     */
    private  String getClassesAbsolutePath(){
        // 得到的是 项目的绝对路径
        String path=this.getClass().getClassLoader().getResource("").getPath();
        //String path=this.getClass().getClassLoader().getResource(".").getPath();
        //String path=this.getClass().getClassLoader().getResource("/").getPath();//报空指针
        String temp = path.replaceFirst("/", "");
        String separator = System.getProperty("file.separator");
        String resultPath = temp.replaceAll("/", separator + separator);
        return resultPath;
    }
    /**
     *得到的是当前类 文件的URI目录,不包括自己
     * ""D:Eclipse3.7JTooluildclassesjavaxorgpath
     * . D:Eclipse3.7JTooluildclassesjavaxorgpath
     - / D:Eclipse3.7JTooluildclasses
     * @return
     */
    private String getCurrentClassPath(){
        //String path=this.getClass().getResource("").getPath();
        //String path=this.getClass().getResource(".").getPath();
        String path=this.getClass().getResource("/").getPath();
        String temp = path.replaceFirst("/", "");
        String separator = System.getProperty("file.separator");
        String resultPath = temp.replaceAll("/", separator + separator);
        return resultPath;
    }
    public static void main(String[] args) {
        System.out.println(getSysPath());
    }
}