SEARCH KEYWORD -- string format


  Remote execute command in Java example

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 ...

   JSch, Example, Distributed system, SSH2     2014-12-12 03:20:19

  The hidden risk of passing slice as function parameter

In Go's source code or other open source libraries, there are lots of cases where a slice pointer is passed to function instead of slice itself. This brings up a doubt why not passing slice directly as its internal is backed by an array pointer to point to underlying data? For example, in log package, the formatHeader function takes a parameter buf as type *[]byte instead of []byte. func (l *Logger) formatHeader(buf *[]byte, t time.Time, file string, line int) {} Let's understand the r...

   GOLANG,SLICE,SLICE POINTER     2020-12-13 06:11:14

  Service discovery with etcd

In previous post, we have talked about etcd and its usage. This post we will cover how to implement server discovery with etcd. Service discovery is to solve one of the most commonly seen scenarios in distributed system where how to find the corresponding target service to talk to. In short, it is to find some server which one can talk to based on some service name. A complete service discovery system include below three key functions: Service registration: A service must register itself to so...

   ETCD,SERVICE DISCOVERY,DEMO,TUTORIAL     2021-03-08 05:36:29

  String.length() vs String.getBytes().length in Java

In Java, String.length() is to return the number of characters in the string, while String.getBytes().length is to return the number of bytes to represent the string with the specified encoding. By default, the encoding will be the value of system property file.encoding, the encoding name can be set manually as well by calling System.setProperty("file.encoding", "XXX"). For example, UTF-8, Cp1252. In many cases, String.length() will return the same value as String.getBytes().length, but in some ...

   Java,UTF8,String,Encoding,Sample     2015-04-01 22:22:23

  Recursive class initialization in Java

When a Java class is referenced and initialized, it has to go through the loading and linking first. Once the loading and linking complete successfully. The class will be initialized. The static variables and constant variables will be initialized during this process. Once the class is initialized, it is ready for use. If when class A is initialized and it is referencing a class B, the class B will also get initialized. But what will happen if class B is referencing class A as well? This is call...

   Java,JVM,class initialization,static final     2015-04-15 21:04:29

  It looks like TechCrunch blocks GoDaddy server access

Recently, I encountered an issue with an app I maintain—it suddenly stopped pulling RSS feeds from TechCrunch. At first, I suspected that the RSS feed URL might have changed. However, after further investigation, I discovered a different story. The URL itself was unchanged, but the results varied depending on where the request was coming from. To troubleshoot, I started by setting up a local web server and running a test with my script to see if it could still pull the RSS feed. The script...

   TECH CRUNCH,GODADDY,AI,BLOCK ACCESS     2024-08-17 12:31:52

  Calculating Token Count for Claude API Using Go: A Step-by-Step Guide

When working with large language models like Claude from Anthropic, understanding how many tokens your input consumes is essential for managing costs and optimizing performance. In this blog, we’ll explore how to calculate token counts for a given input using Go. We’ll use Anthropic’s count_tokens API endpoint, which provides a straightforward way to determine token usage. Prerequisites Before diving in, ensure you have: A working Go environment (installation guide). An Anthro...

   CLAUDE,GO,GOLANG,TOKEN CALCULATION,GUIDE,EXAMPLE     2024-12-23 22:25:29

  Some tricks on PHP session

1. Session timeout problem There is a nuance we found with session timing out although the user is still active in the session.  The problem has to do with never modifying the session variable. The GC will clear the session data files based on their last modification time.  Thus if you never modify the session, you simply read from it, then the GC will eventually clean up. To prevent this you need to ensure that your session is modified within the GC delete time.  You can accomp...

   PHP,Session,Timeout,Solution,Various domain     2015-03-13 07:05:37

  The Greatest Regex Trick Ever (Simplified)

There is a post which is really hot recently which showcased a best ever regular expression trick. In this post, it provides a trick which can be adapted to situations where one wants to match some patterns desired and exclude the patterns undesired. In simple, the trick is : Pattern not desired | (Pattern desired) Then taking the group 1 match of the capturing group of matched. This group will contain the strings matching the desired patterns. Have to say this trick is really neat and brilliant...

   REGULAR EXPRESSION,PROGRAMMING,JAVA     2015-10-01 21:59:05

  Understand unsafe in GoLang

Before going to understand unsafe package in GoLang, the first thing needs to talk about is the pointer in GoLang. If you have a background of C language, you must know what pointer means and its usage. With pointer, you are free to operate any data at memory level which means you have great power, but this means that you have great responsibility as well. That's why it might be considered unsafe in lots of cases. Take a look at a simple example of doubling an integer. package main import "fmt"...

   GOLANG,UNSAFE,ZERO-COPY     2020-03-14 23:18:00

RECENT