I’m rolling my own simple caching solution to improve the UX of a lengthy lookup. The basic outline is that I have a class handling all accountId lookups, and another class called AccountListCache with two variables: a timestamp indicating when it was created, and a List object containing a whole bunch …
Tag: synchronization
sorting files using multithreading in java
I was given an assignment to write all ordered contents of given files into a result.txt. At first, the filenames are split into different Arraylists where each file contains a label in a format #n/N where N is the total number of files. e.g. British explorer James Clark Ross led the first expedition to reach…
Do I need synchronize method Scheduled method?
I have a Spring schedulled tasks which calls the same private method. Do I need to sync this method? Will I have the problem if shedulled tasks runned in the same time? Or will be better to extract it to the prototype component or separate schedulled classes or something else? Answer The default ThreadPoolTas…
how to add synchronization in following lambda exp?
Can synchronized blocks be used for some of the code blocks written in lambda expression . With respect to the following code snippet : Answer It is possible to use synchronized blocks inside a Java Lambda Expression and inside anonymous classes. Note: You have forgotten to add code snippet as no code snippet…
How to synchronize method with HazelCast between two nodes?
There is Spring Boot project. Project works on two nodes. I have method for send message mail with scheduler. The message is sent 2 times, since two nodes are working. How can I use HazelCast to configure the method so that it works once, only by one, more optimal node? There is very little documentation and …
Can a java thread waiting with wait() ,notify itself?
I came across the following e example to implement custom suspend and wait from some website. I am more concerned about the ob1.mysuspend() and ob1.myresume() calls. When my suspend is called then ob1 will be placed into the blocking queue associated with the runnable object it is using. When ob1 calls myresu…
Spring controller how to serve only 1 request each time, and discard other requests received for the same method until first request has finished
So as the title describes I want to achieve the following I want the code to be executed only for 1 request that comes at a time. The execution of the code inside the synchronized block can last about 1 hour. In the mean time I would like each other request that arrives to that method to be cancelled. Is
Multiple thread failed to execute the nonsynchronized code in java
If Thread1 get the lock and start executing the synchronized block, During the same time,Thread2 is free to execute the non-synchronized part of the code which is IntStream.range(0, 5).forEach(x -> System.out.println(“thread Unsafe Zone,”+name)). Unexpectedly,below is what actually happening wh…
Unexpected behaviour of Threads
I am trying to achieve that thread2 should complete first, then thread1, For this O am using join() method. But if I uncomment the System.out.println() present in the try block of thread1 class. then code give null pointer exception. Why in try block I need to add line, it doesn’t make any sense that ad…
How Can I print like below using thread synchronization method?
I have used thread Synchronization method to print ASCII code and its value like below example. Ex:- A 65 B 66 C 67 . . . . Z 90 But the output is this. Following are the two threads. Thread 1 Thread 2 Main What can I do for it without changing main method? Answer This can be solved using