If I have a Java record with 2 properties and I want to define default values for the properties which should be used instead of null. I can either override the getters Or I can achieve much the same thing by overriding the default constructor Both of these seem a bit verbose, is there a more concise way to a…
Tag: java
Hashing runs out of memory, and getting slower and slower over time
I have a GUI desktop application which generates different types of hash (example MD5) for files and directories. Recently, when I was testing with a 1GB test file I recognized that it becomes slower and slower over time. At the first hashing, it takes about 2 seconds for a 1GB file, however later, for the ex…
Why doesn’t Java automatically access the overridden method?
Given two classes, a parent class and a child class: One has a method called greet(), which is private, and the other one defines a method with the same name, only that it is public. Now, as far as I know, the child’s greet() method doesn’t override the parent’s method, because it ‘hid…
Thread not awake when timed wait elapsed in java
I am study wait(long timeout) in java,and in the offcial document I found below description: Some other thread invokes the notify method for this object and thread T happens to be arbitrarily chosen as the thread to be awakened. Some other thread invokes the notifyAll method for this object. Some other thread…
Ensure Maven pulls latest version of release
This question is a little different than the other “checking for latest dependency version” type questions. Let’s say we have a project, DepProjA, that builds and publishes an artifact for our other Java apps to import as a dependency. For example, AppProj1 lists DepProjA as a dependency in …
Creating Constraint layout uisng java file
I am trying to create constraint layout using Mainactivity.java but I am facing some problems. I’m getting the below output. The constraint layout isn’t matching the size of parent. I have created 2 classes 1 is MainActivity.java and another is MyConstraintLayout.Java MyconstraintLayout.java MainA…
Evaluate groovy expression in java class
I am looking to evaluate math expressions from String values using groovy in java code. I have created groovy script like below: The class MyObject is defined as: The code to evaluate the expression is: I keep getting the below exception when I try to run the code: Please suggest the correct approach to achie…
How can I create a button for clickable many times on android?
I triying make a android app for learning but my buttons clickable only once. I can’t click second time. Here is my codes for button. There is the xml codes: And there is java codes: There is generate method: There is variables: Answer After calling generate() the first time password.length() < 16 wi…
Is there any pitfall using mutable set when mapping two repositories by using @OneToMany
I have two repositories mapped by using @OneToMany notation. Let’s say @OneToMany entity is A, and @ManyToOne entity is B. I keep mutableSetOf(B) in entity of A. After I map two of them I had to get first B after checking some properties. But while debugging I realized that order of them comes randomly …
JOOQ – Codegen – How to generate DAOs and POJOs into two differents Maven module
I use JOOQ with a PostgreSQL database. For the moment all the code generated by JOOQ is in the same Maven project. I would like to know if it is possible to separate the JOOQ code generation in two separate Maven modules: in a server module: JOOQ records and DAOs generation in a common module: generation of P…