Skip to content

Repository files navigation

Usage

Gradle

compile group: 'com.github.akurilov', name: 'java-commons', version: '2.3.6'

Library Content

Collections

Circular Buffer

Allows to reuse the buffer for the elements inserting and removing w/o memory copy.

importcom.github.akurilov.commons.collection.CircularBuffer;
importcom.github.akurilov.commons.collection.CircularArrayBuffer;
...
finalvarbuff = (CircularBuffer<String>) newCircularArrayBuffer<>(capacity);
...

Trees

  • Deep copy
importcom.github.akurilov.commons.collection.TreeUtil;
...
finalvarsrcTree = (Map<String, Object>) ...
finalvardstTree = (Map<String, Object>) TreeUtil.copyTree(srcTree);
  • Add branch
finalvarbranch = (Map<String, Object>) ...
TreeUtil.addBranches(dstTree, branch);
  • Deep merge

TODO

  • Reduce a forest into a tree
finalvarforest = (Map<String, Object>) ...
finalvartree = (Map<String, Object>) TreeUtil.reduceForest(forest);

Range

The range described with at least one bound (begin or end position) and optional size.

Concurrency

AsyncRunnable

The entity with the following defined states:

  • INITIAL
  • STARTED
  • SHUTDOWN
  • STOPPED
  • CLOSED

The corresponding methods (start/shutdown/stop/close) are available guaranteeing the thread-safe transition. Each method provides the extension points for user action upon transitions. Also, there are also a pair of await methods intended to block until the instance leaves the STARTED state.

A user should extend the AsyncRunnableBase class.

Throttles

A throttles provide semaphore-like non-blocking functionality. All throttles also support batch permits acquiring.

Rate throttle example:

finalvarrateLimit = 0.1;
finalvarthrottle = (Throttle) newRateThrottle(rateLimit);
...
n = throttle.tryAcquire(10);

Complex weighted throttle example:

finalvarweights = newint[] { 80, 20 }; // permits distribution 80% in the 1st direction vs 20% in the 2nd onefinalvarweightedThrottle = (IndexThrottle) newSequentialWeightsThrottle(weights);
...
if(weightedThrottle.tryAcquire(0)) {
// a permit in the 1st direction is acquired
...
}
...
n = weightedThrottle.tryAcquire(1, 10); // try to acquire up to 10 permits in the 2nd direction

Functional Programming

Partial Functions

TODO

Object I/O

Binary

TODO

Collections

TODO

Expressions

A values input evaluating an expression and returning the result. Utilizing the Java Unified Expression Language functionality.

Current time millis supplying example:

finalvarin = ExpressionInput.<Long>builder()
.expr("${time:millisSinceEpoch()}")
.func("time", "millisSinceEpoch", System.class.getMethod("currentTimeMillis"))
.build();
...
System.out.println(in.get());

Custom random dynamic string example:

finalIntFunction<String> idSupplier = (radix) -> Long.toString(
abs(Long.reverse(currentTimeMillis()) ^ Long.reverseBytes(nanoTime())),
radix
);
finalvarin = ExpressionInput.<String>builder()
.value("idSupplier", idSupplier, IntFunction.class)
.value("radix", 36, int.class)
.expr("${idSupplier.apply(radix)}")
.build();
System.out.println(in.get());

The most interesting feature is the ability to evaluate the expression on the previous expression result:

finalvarin = ExpressionInput.builder()
.expression("${this.last() + 1}%{-1}")
.type(int.class)
.build();
in.get(); // will return 0in.get(); // 1in.get(); // 2
...

In other words, it's possible to calculate each next value using the previous one.

Text

TODO

Math

Includes the XorShift and greatest common divisor methods.

Networking

TODO

Lang

Contains the method void throwUnchecked(final Throwable t) allowing to throw checked exceptions as unchecked ones.

Reflection

Types Comparison

TODO

System

Direct Memory

Thread local direct memory byte buffers cache. Useful for the zero-copy I/O. Instead of allocating the buffer of exact size find the most suitable sized byte buffer in the thread local cache. The cache contains the sequence of buffers with a sizes 1, 2, 4, ..., 16MB. The total count of the buffers in the cache is 25 and their summary size is less than 32MB.

Examples:

MappedByteBufferbbuff;
bbuff = DirectMemUtil.getThreadLocalReusableBuff(0); // will return the byte buffer with the size of 1 bytes (min)bbuff = DirectMemUtil.getThreadLocalReusableBuff(1); // will return the byte buffer with the size of 1 bytesbbuff = DirectMemUtil.getThreadLocalReusableBuff(12345); // will return the byte buffer with the size of 16 KBbbuff = DirectMemUtil.getThreadLocalReusableBuff(1_000_000_000_000L); // will return the byte buffer with the size of 16 MB (max)

Size In Bytes

The class to represent some size data. A size may be formatted into the form like "1.234MB". Also the size may be not fixed but describe some size range with the given bias.

About

Common functionality library used in the java-coroutines and Mongoose

Topics

Resources

Stars

1 star

Watchers

1 watching

Forks

Releases

Packages

Used by

Contributors

Languages