How to parse JSON boolean value?
A boolean is not an integer; 1 and 0 are not boolean values in Java. You’ll need to convert them explicitly: or serialize the ints as booleans from the start.
Java
How can I list the available Cipher algorithms?
Once I have a list of providers, as described in JB Nizet’s post, I still don’t have a list of algorithms. I found that each Provider functions as a Properties object, and the Properties encode the algorithm names. I’m not entirely clear on if this is the correct way to look for them or not, … Read more
package does not exist error!
This works: com/example/model/BearExtra.java com/example/web/Bear.java Now, to compile and run these classes, go to the directory where you can “see” the com folder and do: *nix/MacOS Windows and the following is being printed to the console:
What does “?” mean in Java? [duplicate]
someval = (min >= 2) ? 2 : 1; This is called ternary operator, which can be used as if-else. this is equivalent to Follow this tutorial for more info and usage.
Range of valid character for a base 64 encoding
I am interested in the following:Is there a list of characters that would never occur as part of a base 64 encoded string?For example *. I am not sure if this would occur or not. If the original input actually had * as part of it would that be encoded differently?
Meaning of $? (dollar question mark) in shell scripts
This is the exit status of the last executed command. For example the command true always returns a status of 0 and false always returns a status of 1: From the manual: (acessible by calling man bash in your shell) $? Expands to the exit status of the most recently executed foreground pipeline. By convention an exit status of 0 means success, and non-zero return status … Read more
Recursion vs. Iteration (Fibonacci sequence)
For terseness, Let F(x) be the recursive Fibonacci So your are calling F(8) twice, F(7) 3 times, F(6) 5 times, F(5) 7 times.. and so on So with larger inputs, the tree gets bigger and bigger.
Exception in thread “main” java.lang.NumberFormatException: For input string: “S”
The letter S is not a number. Did you mean to write the number 5? Or did you mean to print the ASCII or Unicode value of the character S?
How can I clear or empty a StringBuilder?
ways that work: Use stringBuilderObj.setLength(0). Allocate a new one with new StringBuilder() instead of clearing the buffer. Note that for performance-critical code paths, this approach can be significantly slower than the setLength-based approach (since a new object with a new buffer needs to be allocated, the old object becomes eligible for GC etc).
How do I get “Press any key to continue” to work in my Java code?
I want the user to enter information again in the first while loop after pressing any key on the keyboard. How do I achieve that? Am I doing something wrong with the while loops. SHould I just have one while loop?