README.md

About streaming-xlsx-writer

The streaming-xlsx-writer is a minimal jar (no runtime dependencies) to enable the output of a single sheet XLSX file on an OutputStream. The file is generated as it is output, there is no buffering beyond that built into a ZipOutputStream and no blocking beyond that inherent in the OutputStream.

Build Status

How to build streaming-xlsx-writer

streaming-xlsx-writer uses Maven as its build tool.

The Maven version must be 3.6.2 or later and the JDK version must be 11 or later (the jar built will be targetted to JDK 11).

Usage

The basic usage pattern is:

1. Create an OutputStream.
2. Create a TableDefinition object to define the formatting you want.
3. Create the XlsxWriter, passing in the TableDefinition.
4. Call startFile, passing in the OutputStream, to output all of the file metadata.
5. Call outputRow for each row required on the worksheet.
6. Call close to end the XLSX document.
7. Call close to close the OutputStream.

It is recommended that try-with-resources be used for closing the XlsxWriter and the OutputStream if possible - though given the intended use as the sink in an asynchronous stream this probably won't be possible.

Do not use the colours or fonts from the sample below, they hurt the eyes.

    String[] DAYS_OF_WEEK = {"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"};

    File file = new File("target/temp/XlsxWriterFileTest.xlsx");
    file.getParentFile().mkdirs();

    try (FileOutputStream fos = new FileOutputStream(file)) {      
      TableDefinition defn = new TableDefinition(null, "My Data", "Jim", true, true
              , new FontDefinition("Comic Sans MS", 15)
              , new FontDefinition("Consolas", 15)
              , new ColourDefinition("FF0000", "00FF00") // Red, Green
              , new ColourDefinition("0000FF", "FF00FF") // Blue, Magenta
              , new ColourDefinition("FFFF00", "00FFFF") // Yellow, Cyan
              , getStandardColumnsDefns()
      );
      
      try (XlsxWriter writer = new XlsxWriter(defn)) {
        writer.startFile(fos);
        for (int i = 1; i < 10; ++i) {
          writer.outputRow(
                  Arrays.asList(
                          i
                          , DAYS_OF_WEEK[i % DAYS_OF_WEEK.length]
                          , LocalDate.of(2022, 5, i)
                          , LocalDateTime.of(1971, 5, i, i, i)
                          , i == 4 ? null : 1.0 / i
                          , i == 2 ? null : i * i
                          , new Date()
                          , "=INDIRECT(\"A\" & ROW()) * INDIRECT(\"D\" & ROW())"
                  )
          );
        }
      }
    }

Logging

The streaming-xlsx-writer currently does no logging. This is because it doesn't actually do many calculations and the unit test coverage is pretty good for them so I thought it best to remove the dependency.

I'm not very fixed to this position, if you can think of a use for logging please file an issue and I will put slf4j back in (no other logging facades will be considered).