JFileIo

Utilities for reading/writing data from/to files in Java. Includes:

• Builders and utility methods for external process execution (i.e. runtime.exec(...))
• Filtered FileVisitor builders which can be passed to Files.walkFileTree(...)
• Rolling file renamer for creating log files or file snapshots/backups
• File reader utility class for reading files using internal cache which is reused between file reads with smart buffer resizing to minimize garbage generated

Take a look at the twg2.io.test package for some examples of how the API can be used.

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Reusable Buffered File Reading

Reuses internal buffers to allow for nearly allocation free file loading on subsequent files read:

String text = FileReadUtil.threadLocalInst().readString(new File(...));

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File Filtering/Recursive Loading:

Example - recursively load files filtered by directory and file extension:

public static List<Path> listFiles(Path projectDir) throws IOException {
	FileVisitorUtil.Builder visitorBldr = new FileVisitorUtil.Builder();
	visitorBldr.getPreVisitDirectoryFilter()
		.addDirectoryNameFilters(false, "/debug", "/tasks", "/src", "/tests");
	visitorBldr.getVisitFileFilter()
		.addFileExtensionFilters(true, new String[] { ".java", ".txt", ".properties" })
		.setTrackMatches(true);

	FileVisitorUtil.Cache visitorCache = visitorBldr.build();

	Files.walkFileTree(projectDir, visitorCache.getFileVisitor());

	return visitorCache.getVisitFileFilterCache().getMatches();
}

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Process Execution:

Example - run a process asynchronously:

public static void runCommand() throws IOException {
	Runtime runtime = Runtime.getRuntime();
	LogService log = new LogServiceImpl(Level.ALL, System.out, LogPrefixFormat.NONE);
	ProcessIoStreamFactory streamFactory = new ProcessIoStreamFactory.MemoryStreams();
	OutputStream outStream = streamFactory.openOutputStream();
	OutputStream errStream = streamFactory.openErrorOutputStream();

	ExecuteCmd exeCmd = ExecuteCmd.execAsync("...", runtime, outStream, errStream, log);

	// do cool stuff with the resulting output and error streams
	// or wait for the task to complete and get the result
	ExecuteCmd.Result result = ExecuteCmd.finishSync(exeCmd);
}