Groovy file writeline

Improve this answer. Szymon Stepniak Szymon Stepniak Thanks a lot, very helpful. This answer is particularly wrong, using Java standard file class will only work if the node step is allocated to the master, if it ends up on a slave, then standard file will fail Reason for this is that all pipeline code is executed on the master, see stackoverflow.

So use writeFile and it is guaranteed work! THanks JonS for your input! I haven't took it into account. Answer update to not confuse other people. Sign up or log in Sign up using Google.

Sign up using Facebook. Groovy provides easier classes to provide the following functionalities for files. The following example will output all the lines of a text file in Groovy. The method eachLine is in-built in the File class in Groovy for the purpose of ensuring that each line of the text file is read. The File class is used to instantiate a new object which takes the file name as the parameter. It then takes the function of eachLine, puts it to a variable called line and prints it accordingly.

If you want to get the entire contents of the file as a string, you can use the text property of the file class. Oh yeah, except that Groovy also has this nice metaprogramming ability built in, which among other things, lets you write println instead of System.

This similarity is way more than skin deep and allows Java programmers to get traction with Groovy very quickly. And just like Python programmers are always looking for the pythonic way to do stuff, there is Groovy that looks like Java, and then there is… groovier Groovy.

This solves the same problem but uses Groovy's with method to make the code more DRY "don't repeat yourself" and to automate closing the input file:. What's between. Notice that you don't need to write myScanner. Also the with gets rid of the need to code myScanner. Note the "file not found" exception; this is because there isn't a file called example. Note also that the files are from things like java. Remember that true after the file name means "append to the file," so you can run this a few times:.

Groovy isn't always shorter! The Apache Groovy site has a lot of great documentation. Another great Groovy resource is Mr. And a really great reason to learn Groovy is to learn Grails , which is a wonderfully productive full-stack web framework built on top of excellent components like Hibernate, Spring Boot, and Micronaut.

Read and write files with Groovy Opensource. Filter the lines from this File, and write them to the given writer based on the given closure predicate. Append binary data to the file. See File append java. Create a new PrintWriter for this file, using specified charset. Creates a buffered writer for this file, writing data without writing a BOM, using a specified encoding. Helper method to create a buffered writer for a file. Renames the file. It's a shortcut for File renameTo File.

Synonym for write text, charset allowing: myFile. Iterates through this file line by line, splitting each line using the given regex separator.

For each line, the given closure is called with a single parameter being the list of strings computed by splitting the line around matches of the given regular expression. Finally the resources used for processing the file are closed. Iterates through this file line by line, splitting each line using the given separator Pattern. For each line, the given closure is called with a single parameter being the list of strings computed by splitting the line around matches of the given regular expression Pattern.

Iterates through this file line by line, splitting each line using the given regex separator Pattern. Convenience method for File traverse java. Map, groovy. Closure when no options to alter the traversal behavior are required. Invokes the closure specified with key 'visit' in the options Map for each descendant file in this directory tree. Closure allowing the 'visit' closure to be included in the options Map rather than as a parameter. The traversal can be adapted by providing various options in the options Map according to the following keys: type A FileType enum to determine if normal files or directories or both are processed preDir A Closure run before each directory is processed and optionally returning a FileVisitResult value which can be used to control subsequent processing.

Particularly useful when strict depth-first traversal is required. Object method. If set, any candidates which match won't be visited. Must not be set if 'excludeFilter' is set sort A Closure which if set causes the files and subdirectories for each directory to be processed in sorted order.

Note that even when processing only files, the order of visited subdirectories will be affected by this parameter. Create a new DataInputStream for this file and passes it into the closure. This method ensures the stream is closed after the closure returns.

Create a new DataOutputStream for this file and passes it into the closure. Create a new InputStream for this file and passes it into the closure. Create a new ObjectInputStream for this file and pass it to the closure. Create a new ObjectInputStream for this file associated with the given class loader and pass it to the closure.

Create a new ObjectOutputStream for this file and then pass it to the closure. Creates a new OutputStream for this file and passes it into the closure. Create a new PrintWriter for this file which is then passed it into the given closure. This method ensures its the writer is closed after the closure returns. Create a new PrintWriter with a specified charset for this file. The writer is passed to the closure, and will be closed before this method returns.

Create a new BufferedReader for this file and then passes it into the closure, ensuring the reader is closed after the closure returns. Create a new BufferedReader for this file using the specified charset and then passes it into the closure, ensuring the reader is closed after the closure returns.

Creates a new BufferedWriter for this file, passes it to the closure, and ensures the stream is flushed and closed after the closure returns. The writer will use the given charset encoding. Create a new BufferedWriter for this file in append mode. The writer is passed to the closure and is closed after the closure returns. Create a new BufferedWriter which will append to this file. The writer is passed to the closure and will be closed before this method returns.

Write the text to the File. Write the text to the File, using the specified encoding. Overview Package Class Index. File asWritable Converts this File to a Writable. File asWritable String encoding Allows a file to return a Writable implementation that can output itself to a Writer stream. Object eachLine Closure closure Iterates through this file line by line. Object eachLine int firstLine, Closure closure Iterates through this file line by line.

Object eachLine String charset, Closure closure Iterates through this file line by line. Object eachLine String charset, int firstLine, Closure closure Iterates through this file line by line.

Writable filterLine Closure closure Filters the lines of a File and creates a Writable in return to stream the filtered lines. Writable filterLine String charset, Closure closure Filters the lines of a File and creates a Writable in return to stream the filtered lines.