Java library that gives you the ETA and displays a progress bar when you process a batch of data.

The available metrics are:

• The progression percentage (the numeric value and a cool progress bar)
• The processing speed
• The ETA: when will the process be finished?

Clone this github repository, launch mvn clean install and add the following maven dependency to your project:

<dependency>
  <groupId>com.vdurmont</groupId>
  <artifactId>etaprinter</artifactId>
  <version>2.0.0</version>
</dependency>

You can find a working example in the examples directory.

Source source = // Your source of elements (your DAO for example)

// The total number of elements you will process
long total = source.size();

// Init the printer
ETAPrinter printer = ETAPrinter.init(total);

while(source.hasNext()) {
  List<Element> elements = source.getNextBatch(); // Get the next batch of elements to process

  process(elements); // That is your business logic and it may take some time

  // We update the ETA by giving the number of elements that were processed since the last update
  printer.update(elements.size());
}

There are a few options that you can choose when you initialize the printer:

• ETAPrinter.init(long total)
• ETAPrinter.init(String elementName, long total)
• ETAPrinter.init(long total, OutputStream stream, boolean closeStream)
• ETAPrinter.init(String elementName, long total, OutputStream stream, boolean closeStream)

Parameters:

• total: total number of elements that are going to be processed
• elementName: the name of the element
  If this parameter is given, the speed will be printed with the following format: 42 [elementName]/s. Else, it will be 42/s.
• stream: the OutputStream where the ETA is printed
  Default value is System.out.
• closeStream: if true, the stream will be closed when the process will end (the number of processed elements will be greater or equal to the total number of elements). Default is false.