JCEKS stands for Java Cryptography Extension KeyStore and it is an alternative keystore format for the Java platform. Storing keys in a KeyStore can be a measure to prevent your encryption keys from being exposed. Java KeyStores securely contain individual certificates and keys that can be referenced by an alias for use in a Java program.The process of storing and loading different entries in JCEKS is similar to what JKS does. So please refer to the article Different types of keystore in Java -- JKS. Change the keystore type from JKS to JCEKS accordingly when calling KeyStore.getInstance().In ...

After many years, people are still discussing whether Erlang is a small language. People have all sorts of doubt about it, but with the appearance of WhatsApp, we may change our mind.What is WhatsApp, from its official website:WhatsApp Messenger is a cross-platform mobile messaging app which allows you to exchange messages without having to pay for SMS.The more funny thing is the main developer of WhatsApp Rick Reed worked in Yahoo and SGI before he joined WhatsApp and he didn't have any knowledge about Erlang at that time:Joined WhatsApp in 2011，New to ErlangLater in another article:Join...

JDK provides a command line tool -- keytool to handle key and certificate generation. This tool has a set of options which can be used to generate keys, create certificates, import keys, install certificate and export certificates etc. In this tutorial, we will show how to create certificate chain using keytool. If you want to understand how to create certificate chain programmably, please refer to Generate certificate in Java -- Certificate chain.To begin, we first generate a key pair which will be used as the CA, ts private key will be used to sign the certificate it issues.keytool -gen...

Writing runnable code is the essential skill of a programmer, writing understandable comment is also a skill a programmer should acquire. There is some famous saying that bad comment is worth than no comment. Usually your code will be maintained by other people, if you provide them some difficult to understand or misguided comments, this will be nightmare to them. While at some other time, programmers may put some funny comments in their codes which may make others laugh. Today we share some comments which are full of humor.1. Send some warning to maintainer// // Dear maintainer...

Multithreading as a widespread programming and execution model allows multiple threads to exist within the context of a single process. These threads share the process' resources but are able to execute independently. The threaded programming model provides developers with a useful abstraction of concurrent execution. However, perhaps the most interesting application of the technology is when it is applied to a single process to enable parallel execution on a multiprocessor system.Many programmers don't know how to use multithreading correctly, and we often get some advice from people regardin...

<tgmath.h> is a header provided by the standard C library,introduced in C99 to allow easier porting of Fortran numerical software to C.Fortran, unlike C, provides “intrinsic functions”, which are a part of the language and behave more likeoperators. While ordinary (“external”) functions behave similarly to C functions with respect to types(the types of arguments and parameters must match and the restult type is fixed), intrinsic functions accept arguments of several types and their return type may depend on the type of their arguments.For example Fortran 77 provid...

Frequently there is a need to logon to a remote system and run some commands or programs to get the output, many software can serve this purpose such as putty and gitshell.These software usually provide secure access to the remote system. But have you ever wondered what to do if you need to run commands on many different systems at the same time and get all these results back at a single place? Especially in big data era, many tasks may run on different distributed systems and you want o have a single place to accumulate the result.In this post, we will introduce a Java library which can help ...

JKS is Java Keystore, a proprietary keystore type designed for Java. It can be used to store private keys and certificates used for SSL communication, it cannot store secret keys however. The keytool shipped with JDKs cannot extract private keys stored on JKS. This type of keystore usually has an extension of jks.Next we will show how to operate the JKS keystore with pure Java code.Create JKS keystoreThe simplest method to create a JKS keystore to create an empty keystore. We can first get an instance of KeyStore and then load a null keystore. After loading the null keystore, we just need to c...