My brain is starting to hurt thinking about this, is it as simple as: Answer Something like:
How do I tell if an empty line has been read in with a BufferedReader?
I’m reading in a text file formated like So I need to keep try of whether I’m in a definition or not based on when I reach those emtpy lines. Thing is, BufferedReader discards n characters, and somehow comparing that empty line to String “” is not registering like I thought it would. H…
Good way to get *any* value from a Java Set?
Given a simple Set<T>, what is a good way (fast, few lines of code) to get any value from the Set? With a List, it’s easy: But, with a Set, there is no .get(…) method because Sets are not ordered. Answer A Set<T> is an Iterable<T>, so iterating to the first element works: Guava h…
Generate x509certificate certpath in JAVA
I successfully make X.509 certificate from certificate request. However, I need to insert CERT Path informatin in the X.509 certificate. I know that I have to use CertPathBuilder method but I don’t know how to use it. could you give me an code example that suitable for the following code? Answer The bel…
Delete all files with an extension using Java
I’m (relatively) new to Java and I’m trying to implement a .jar that runs a list of commands that in Windows XP’s command prompt it would be: My (failed) attempt: I screwed somewhere around that “get(i)”, but I think I’m pretty close to my goal now. I ask for your help and …
implementing a lazy Supplier in java
What is the right paradigm or utility class (can’t seem to find a preexisting class) to implement a lazy supplier in Java? I want to have something that handles the compute-once/cache-later behavior and allows me to specify the computation behavior independently. I know this probably has an error but it…
UsageMemory threashold in JConsole
I am looking into how to use JConsole to detect memory leaks. I see that in Memory Pool in my MBeans I can define UsageThreashold for my Tenured Generation. So if my application exceeds this threashold the heap memory becomes red in the Memory tab. Question: How does this help? I mean how am I supposed to use…
Error in Java Import statement “The import javax.validation.constraints.NotNull cannot be resolved”
After developing Spring roo project, I found following errors in class: I am using STS 3.1.0.RELEASE How can this be rectified? Answer The jar containing this class must be added to the build path of your project: http://mvnrepository.com/artifact/javax.validation/validation-api/1.0.0.GA
SQLDeveloper runs query but getting a “ORA-00979: Not a Group By expression” from hibernate
I have data that looks something like this: And a query that works fine in Oracle SQL Developer (It returns data averaged over 15 second periods): but when I plug it into my java code, I get an error: The actual query string I use in the Jave looks more like this: and the parameters are set by calling: Anyone
Get Username from Amazon Access Key in Java
Is there a way to get the User Name attached to the Access Key for the credentials you’re using to access AWS via Java? I would like to be able to get the User Name that’s defined in the IAM Users section so that I can setup user-specific buckets/folders and then dynamically point the script to th…