zip()方法中第三个参数""是什么意思，以及代码中的base是什么意思

Question

import java.io.*;
import java.util.zip.*;

public class MyZip {
private void zip(String zipFileName, File inputFile) throws Exception {
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
zipFileName));
zip(out, inputFile, ""); //第三个参数“”是什么意思
System.out.println("压缩中…");
out.close();
}

private void zip(ZipOutputStream out, File f, String base)
        throws Exception { 
    if (f.isDirectory()) { 
        File[] fl = f.listFiles(); 
        out.putNextEntry(new ZipEntry(base + "/"));   //以下几行代码base是什么意思
        base = base.length() == 0 ? "" : base + "/"; 
        for (int i = 0; i < fl.length; i++) {
            zip(out, fl[i], base + fl[i]);
        }
    } else {
        out.putNextEntry(new ZipEntry(base)); 

        FileInputStream in = new FileInputStream(f);
        int b;
        System.out.println(base);
        while ((b = in.read()) != -1) { 
            out.write(b);
        }
        in.close();
    }
}

public static void main(String[] temp) { 
    MyZip book = new MyZip(); 
    try {

        book.zip("hello.zip", new File("src"));
        System.out.println("压缩完成"); 
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

}

Answer 1

base就是个你传入的路径，“”就是传入空内容的路径， base = base.length() == 0 ? "" : base + "/"; 三目运算符，判断如果传入的base内容为空串，base 就等于"/";