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java zip filesystem reading zip entries

SO, from what I've gathered, one is supposed to be able to create a filesystem from a zip from java 7 and beyond. I'm trying this, the ultimate goal is to use the File object and access these files, just as if I accessed an unzipped file.
import java.io.File;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.nio.file.*;
import java.util.*;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
public class MainZipTest {
public static void main(String[] args) throws IOException, URISyntaxException {
Map<String, String> env = new HashMap<>();
env.put("read", "true");
File file = new File("C:/pathtoazip/data.zip");
URI uri = file.toURI();
String path = "jar:" + uri;
FileSystem fs = FileSystems.newFileSystem(URI.create(path), env);
for (Path p : fs.getRootDirectories()) {
System.out.println("root" + p);
//says "/"
System.out.println(new File(p.toString()).exists());
for (File f : new File(p.toString()).listFiles())
System.out.println(f.getAbsolutePath());
//lists the contents of my c drive!
}
System.out.println(new File("somefile.txt").exists());
System.out.println(fs.getPath("somefile.txt").toFile().exists());
System.out.println(new File("/somefile.txt").exists());
System.out.println(fs.getPath("/somefile.txt").toFile().exists());
}
}
it all prints "false". What am I doing wrong here? Or am I wrong in my assumption that I can access these files through the File object? If so, how does one access them?

Path was introduced as generalization of File (disk file). A Path can be inside a zip file, an URL, and more.
You can use Files with Path for similar File functionality.
for (Path p : fs.getRootDirectories()) {
System.out.println("root: " + p);
System.out.println(Files.exists(p));
Files.list(p).forEach(f -> System.out.println(f.toAbsolutePath()));
}
Note that a Path, like from a zip will maintain its actual file system view (fs, the zip).
So avoid File.

Writing to Google Persistent DIsk

I've written some java code that creates a CSV file at the mount point of a disk I have attached to a Google Compute instance. I run the script in the form of a SQL stored procedure from the instance that the disk is attached to. The issue is that at the mount point, a "lost+found" folder is created where I would expect to find my CSV file. What am I doing wrong? Thank you for your time! The code is similar to as follows:
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.FileOutputStream;
public class file_write {
public static void main(String[] args) throws IOException{
String filePath = "/mnt/point/file.csv";
// Creates file in mount point
File myFile = new File(filePath);
myFile.getParentFile().mkdirs();
myFile.createNewFile();
FileWriter stringWriter = new FileWriter(myFile);
for(int i = 0; i < 100000; i++) {
stringWriter.write(i + ", ");
stringWriter.write("something");
stringWriter.write(System.lineSeparator());
}
stringWriter.close();
}
}

File Not Found Exception - Can't see the issue

I've tried directly linking using the entire path but that hasn't solved it either.
package eliza;
import java.io.*;
public class Eliza {
public static void main(String[] args) throws IOException {
String inputDatabase = "src/eliza/inputDataBase.txt";
String outputDatabase = "src/eliza/outputDataBase.txt";
Reader database = new Reader();
String[][] inputDB = database.Reader(inputDatabase);
String[][] outputDB = database.Reader(outputDatabase);
}
}
Here is the reader class:
package eliza;
import java.io.FileReader;
import java.io.BufferedReader;
import java.io.IOException;
public class Reader {
public String[][] Reader(String name) throws IOException {
int length = 0;
String sizeLine;
FileReader sizeReader = new FileReader(name);
BufferedReader sizeBuffer = new BufferedReader(sizeReader);
while((sizeLine = sizeBuffer.readLine()) != null) {
length++;
}
String[][] database = new String[length][1];
return (database);
}
}
Here's a photo of my directory. I even put these text files in the "eliza" root folder: here
Any ideas?

Since you are using an IDE, you need to give the complete canonical path. It should be
String inputDatabase = "C:\\Users\\Tommy\\Desktop\\Eliza\\src\\eliza\\inputDataBase.txt";
String outputDatabase = "C:\\Users\\Tommy\\Desktop\\Eliza\\src\\eliza\\outputDataBase.txt";
The IDE is probably executing the bytecode from its bin folder and cannot find the relative reference.

give the exact path like
String inputDatabase = "c:/java/src/eliza/inputDataBase.txt";

you have not given the correct path, Please re check
try
{BASE_PATH}+ "Eliza/src/inputDataBase.txt"

The source directory tree isn't generally present during execution, so files that are required at runtime shouldn't be put there ... unless you're going to use them as resources, in which case their pathname is relative to the package root, and does not begin with 'src', and the data is accessed by a getResourceXXX() method, not via a FileInputStream.

Java UnZipping a zipped .app back to .app (OS X)

In my auto updater application i am downloading a zipped file that contains the new MyApp.app application file. So i am downloading MyApp.zip.. Then i use this following class to try and unzip it:
package update;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import java.util.zip.ZipInputStream;
public class UnZip {
public static final void copyInputStream(InputStream in, OutputStream out)
throws IOException
{
byte[] buffer = new byte[1024];
int len;
while((len = in.read(buffer)) >= 0)
out.write(buffer, 0, len);
in.close();
out.close();
}
public static final void unZipIt(String F1, String F2) {
Enumeration entries;
ZipFile zipFile;
try {
zipFile = new ZipFile(F1);
entries = zipFile.entries();
while(entries.hasMoreElements()) {
ZipEntry entry = (ZipEntry)entries.nextElement();
if(entry.isDirectory()) {
// Assume directories are stored parents first then children.
System.err.println("Extracting directory: " + entry.getName());
// This is not robust, just for demonstration purposes.
(new File(entry.getName())).mkdirs();
continue;
}
System.err.println("Extracting file: " + entry.getName());
copyInputStream(zipFile.getInputStream(entry),
new BufferedOutputStream(new FileOutputStream(entry.getName())));
}
zipFile.close();
} catch (IOException ioe) {
System.err.println("Unhandled exception:");
ioe.printStackTrace();
return;
}
}
}
However after the unzip the application wont launch.. any ideas?

Your executable file is most likely not flagged as executable. The trick is that .app "files" are in fact directories, so making them executable serves no practical purpose, you need to find the actual binary.
To do that, you need to open ./myApp.app/Contents/Info.plit and look for the CFBundleExecutable key: the associated string is the path of the executable file, relative to ./myApp.app/Contents/MacOS, I believe.
Once you've found that file, chmod +x it, and check whether your application still fails to start.
If it doesn't, problem solved.
If it does, try and open your application from the terminal through the open ./myApp.app command. If anything odd is printed, update your question with it and let us know what that was.
If all else fails, look into the Console application for interesting log entries - you can search for your application's name, see if anything comes up.

Eclipse shows errors when i write information in xml file

I use the JDOM library. When I write information into an xml file, Eclipse shows errors. The system cannot find the path specified. I try to create the file in the "language" folder. How can I create the folder automatically when I write info into this file? I think the error is in this line:
FileWriter writer = new FileWriter("language/variants.xml");
Here is my code:
package test;
import java.io.FileWriter;
import java.util.LinkedList;
import org.jdom2.Attribute;
import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.output.Format;
import org.jdom2.output.XMLOutputter;
class Test {
private LinkedList<String> variants = new LinkedList<String>();
public Test() {
}
public void write() {
Element variantsElement = new Element("variants");
Document myDocument = new Document(variantsElement);
int counter = variants.size();
for(int i = 0;i < counter;i++) {
Element variant = new Element("variant");
variant.setAttribute(new Attribute("name",variants.pop()));
variantsElement.addContent(variant);
}
try {
FileWriter writer = new FileWriter("language/variants.xml");
XMLOutputter outputter = new XMLOutputter();
outputter.setFormat(Format.getPrettyFormat());
outputter.output(myDocument,writer);
writer.close();
}
catch(java.io.IOException exception) {
exception.printStackTrace();
}
}
public LinkedList<String> getVariants() {
return variants;
}
}
public class MyApp {
public static void main(String[] args) {
Test choice = new Test();
choice.write();
}
}
Here is the error:
java.io.FileNotFoundException: language\variants.xml (The system cannot find the path specified)
at java.io.FileOutputStream.open(Native Method)
at java.io.FileOutputStream.<init>(FileOutputStream.java:212)
at java.io.FileOutputStream.<init>(FileOutputStream.java:104)
at java.io.FileWriter.<init>(FileWriter.java:63)
at test.Test.write(MyApp.java:31)
at test.MyApp.main(MyApp.java:49)`enter code here

As the name suggests FileWriter is for writing to file. You need to create the directory first if it doesnt already exist:
File theDir = new File("language");
if (!theDir.exists()) {
boolean result = theDir.mkdir();
// Use result...
}
FileWriter writer = ...

For creating directories you need to use mkdir() of File class.
Example:
File f = new File("/home/user/newFolder");
f.mkdir();
It returns a boolean: true if directory created and false if it failed.
mkdir() also throws Security Exception if security manager exists and it's checkWrite() method doesn't allow the named directory to be created.
PS: Before creating directory, you need to validate if this directory already exists or not by using exists() which also returns boolean.
Regards...
Mr.777