nio – Page 3 – Tarik Billa

What is the difference between Tomcat’s BIO Connector and NIO Connector?

April 9, 2023 by Tarik

NIO and Comet are completely unrelated: you can mix-and-match them. Using the NIO (or APR for that matter) connector allows you to handle more requests with fewer threads due to the threading model. See http://tomcat.apache.org/tomcat-7.0-doc/config/http.html#Connector_Comparison for a comparison between the Connectors. Comet (and Websocket) have a completely different dispatch model which requires a different application … Read more

How to get the path string from a java.nio.Path?

April 9, 2023 by Tarik

Use: Paths.get(…).normalize().toString() Another solution woul be: Paths.get(…).toAbsolutePath().toString() However, you get strange results: Paths.get(“/tmp”, “foo”).toString() returns /tmp/foo here. What is your filesystem?

Alternative to File.deleteOnExit() in Java NIO?

April 9, 2023 by Tarik

Short Answer You can’t delete arbitrary files in Java NIO, but you can use the StandardOpenOption.DELETE_ON_CLOSE when opening a new stream, which will delete the file as soon as the stream closes, either by calling .close() (including from a try-with-resources statement) or the JVM terminating. For instance: Files.newOutputStream(Paths.get(“Foo.tmp”), StandardOpenOption.DELETE_ON_CLOSE); Long Answer After a great deal … Read more

How to overwrite file via java nio writer?

April 3, 2023 by Tarik

You want to call the method without any OpenOption arguments. Files.write(path, content.getBytes()); From the Javadoc: The options parameter specifies how the the file is created or opened. If no options are present then this method works as if the CREATE, TRUNCATE_EXISTING, and WRITE options are present. In other words, it opens the file for writing, … Read more

Java best practice: Class with only static methods

April 1, 2023 by Tarik

I would say you’re doing it right. Apart of that, some advices for your utility class: Make sure it doesn’t have any state. This is, there’s no field in the class unless it’s declared static final. Also, make sure this field is immutable as well e.g. Strings. Make sure it cannot be a super class … Read more

Wrapping a ByteBuffer with an InputStream

April 1, 2023 by Tarik

There seem to be some bugs with the implementation referred to by Thilo, and also copy and pasted on other sites verbatim: ByteBufferBackedInputStream.read() returns a sign extended int representation of the byte it reads, which is wrong (value should be in range [-1..255]) ByteBufferBackedInputStream.read(byte[], int, int) does not return -1 when there are no bytes … Read more

Java.nio: most concise recursive directory delete

March 25, 2023 by Tarik

You can combine NIO 2 and the Stream API. Path rootPath = Paths.get(“/data/to-delete”); // before you copy and paste the snippet // – read the post till the end // – read the javadoc to understand what the code will do // // a) to follow softlinks (removes the linked file too) use // Files.walk(rootPath, … Read more

Java access files in jar causes java.nio.file.FileSystemNotFoundException

March 5, 2023 by Tarik

A FileSystemNotFoundException means the file system cannot be created automatically; and you have not created it here. Given your URI, what you should do is split against the !, open the filesystem using the part before it and then get the path from the part after the !: final Map<String, String> env = new HashMap<>(); … Read more

When to use ** (double star) in glob syntax within JAVA

February 26, 2023 by Tarik

The javadoc for FileSystem#getPathMatcher() has some pretty good examples and explanations *.java Matches a path that represents a file name ending in .java *.* Matches file names containing a dot *.{java,class} Matches file names ending with .java or .class foo.? Matches file names starting with foo. and a single character extension /home/*/* Matches /home/gus/data on … Read more

How to access a sub-file/folder in Java 7 java.nio.file.Path?

February 20, 2023 by Tarik

Use the resolve method on Path. There are two methods with this name. One takes a relative Path and the other a String. It uses the Path on which it is called as a parent and appends the String or relative Path appropriately. Path parent = Paths.get(“c:\\tmp”); Path child = parent.resolve(“child”);