ahmeni posted:

Are heap dumps with tools like jmap very useful from our operations non-developer perspective?

mister_gosh posted:

Is there a way, using the java.awt.Desktop, or something very similar, to select a file?

I can use Desktop.open() to open to a file location in Windows, but then I want it to select a particular file in that directory.

Rexxed posted:

Seems like you can do that by launching explorer with the /select option:
explorer.exe /select,"C:\Folder\subfolder\file.txt"

Copied from: http://stackoverflow.com/questions/13680415/how-to-open-explorer-with-a-specific-file-selected

BexGu posted:

Any one know of any java classes that do the same things (or similar) to this Python script? (Creating Human readable UUIDs)

https://github.com/zacharyvoase/humanhash

mister_gosh posted:

Is there a way, using the java.awt.Desktop, or something very similar, to select a file?

I can use Desktop.open() to open to a file location in Windows, but then I want it to select a particular file in that directory.

PlesantDilemma posted:

Hello! I'm a PHP developer who would like to get into Java web programming. I'm just not sure where to start. The Java world is pretty huge. Do I need to learn Ant, Maven, or Gradle? Should I start with one of the many web frameworks out there, or do something more low level? And what is low level? Servlets? JSP? I'm not sure what the difference is. And if I pick a framework, it seems that some need a container like tomcat to run and others can be their own container, is that a big factor?

I learned Java syntax in school but we did simple GUI and data structure stuff, we never needed a build tool besides what Eclipse could do for us. Trying to make something real in Java looks like a daunting task. I want to stick with web stuff since that is what I know, but I don't know where to start.

mister_gosh posted:

...(all users are Windows)...

lamentable dustman posted:

Java and its eco system is loving huge and trying to digest it all at once isn't really feasible. Pick a project you want to do (or port one of your PHP projects) and just bang away at it and pick it up as you.

To answer your questions I would just start with Maven, Ant can be learned in a pinch if needed, I haven't used Gradle so I can't comment on that.

Servlets are pretty much the lowest you can go. A JSP is a view and would be close to your .php file but it is generally frowned upon to put processing in them, you should use JSTL (I think, haven't been in the web game outside of services in a while)

Just use Tomcat, it will suit must of your needs. Once you go corporate you may need to switch to JBoss but Tomcat will be a good base.

PlesantDilemma posted:

Hello! I'm a PHP developer who would like to get into Java web programming. I'm just not sure where to start. The Java world is pretty huge. Do I need to learn Ant, Maven, or Gradle? Should I start with one of the many web frameworks out there, or do something more low level? And what is low level? Servlets? JSP? I'm not sure what the difference is. And if I pick a framework, it seems that some need a container like tomcat to run and others can be their own container, is that a big factor?

I learned Java syntax in school but we did simple GUI and data structure stuff, we never needed a build tool besides what Eclipse could do for us. Trying to make something real in Java looks like a daunting task. I want to stick with web stuff since that is what I know, but I don't know where to start.

fletcher posted:

I haven't used it before, but the Play Framework seems like a good way to hit the ground running.

Hard NOP Life posted:

Agreed with everything you just said but I would recommend GlassFish over Tomcat for someone just starting out today. The concepts you learn will port over well to any of the other servers, butt the admin console is a lot easier to use and understand at first and don't require loving around with XML configs until you need to configure very advanced features. ALso there are plugins for it just like Tomcat in every IDE which will help with deploying your projects straight from the IDE.

fletcher posted:

I haven't used it before, but the Play Framework seems like a good way to hit the ground running.

Hard NOP Life posted:

Holy poo poo man Play Framework is the exact opposite of baby's first Java web, it's a huge framework of java, scala, sbt and plugins. It runs its own webserver instead of using the standard WAR packaging system, it's as far away from the standard java ecosystem as you can get.

Learn Servlets and JSPs first they are the building blocks that everything else is built on, then get into frameworks like Spring, Struts 2 or Wicket.

fletcher posted:

Yeah you're right, probably not the best way to start out. From what I had heard about it it kinda sounded like Django for Java.

Hard NOP Life posted:

Learn Servlets and JSPs first they are the building blocks that everything else is built on, then get into frameworks like Spring, Struts 2 or Wicket.

PlesantDilemma posted:

I'm gonna go with this. If anyone knows some good servlet/jsp tutorials feel free to post them. I'm gonna fire up Eclipse and see what google search can teach me.

Hard NOP Life posted:

Yeah Play is different in that it tries to break away from the Java EE system of requiring an application server to host your application by bundling it's own web stack. I'm convinced that the motivations for it amount to nothing more than "gently caress You Dad, our way is cooler!", but that just might be my YOSPOS leaking, either way it looks cool and I'll have to delve more deeply into in the near future.

Tamba posted:

What you want are unchecked exceptions.
You might also want to read this before you actually decide to use them though: http://docs.oracle.com/javase/tutorial/essential/exceptions/runtime.html

Woodsy Owl posted:

Good deal, thanks for those. I learned a lot reading through, and now I have some good bookmarks. It looks like the data structures already provided in the standard library throw exceptions that inherit RuntimeException, which makes them unchecked.

Zaphod42 posted:

Zaphod42 posted:

Gravity Pike posted:

The Guava Throwables library has a nifty convenience operation for this use case:

Java code:

try {
    myDangerousOperation();
} catch (Exception e) {
    Throwables.propagate(e);
}

which basically expands to:

Java code:

try {
    myDangerousOperation();
} catch (Exception e) {
    if (e instanceof RuntimeException) {
        throw e;
    } else {
        throw new RuntimeException(e);
    }
}

Kilson posted:

Of course, in cases where you *know* that you won't actually throw the checked exception (and there are many such cases), then do what you want. It just looked like you were advocating the Spring approach of wrapping *all* exceptions as runtime, which I still say loving sucks.

FateFree posted:

What's wrong with having only runtime exceptions? Thats how new languages like c# handle exceptions. Checked exceptions have caused more pain and harm and general misuse than any other feature. All it takes is a @throws declaration in the comments and anyone whose calling your method can choose to handle a runtime exception or ignore it.

quote:

Statement stmt2 = con.createStatement();
String query2;
ResultSet rs2;

// Asking for the Folder of the picture for image generation
query2 = "Select Folder FROM categories WHERE CategoryNo = "+category+"";
rs2 = stmt2.executeQuery(query2);
out.println("<img src=\"http://galleryurl/");
while (rs2.next()) {
String folder = rs2.getString("Folder");
out.println(""+folder+ "/");
}

Statement stmt3 = con.createStatement();
String query3;
ResultSet rs3;

// Asking for the Name of the picture for image generation
query3 = "Select FileName FROM pictures WHERE PictureNo = "+picture+"";
rs3 = stmt3.executeQuery(query3);
while (rs3.next()) {
String fileName = rs3.getString("FileName");
out.println(""+fileName+ "\">");
}

quote:

<img src="http://galleryurl/folder/BIGshot.bmp">

fletcher posted:

Shouldn't mix database access and presentation like that. Also need to close your database resources when you're done with them using a try/catch/finally. Also don't use string concatenation to build SQL statements, use prepared statements instead to avoid SQL injection attacks.

quote:

try {
Statement stmt = con.createStatement();
ResultSet rs;
stmt = con.createStatement();
rs = stmt.executeQuery("SELECT statistics.accessdata, pictures.ShortName, categories.ShortName FROM jcg ORDER BY AccessCount");
ResultSetMetaData rsmd = rs.getMetaData();
int numberOfColumns = rsmd.getColumnCount();
int rowCount = 0;
while (rs.next()) {
out.println("Row " + (++rowCount) + ": ");
for (int i = 1; i <= numberOfColumns; i++) {
out.print(" Column " + i + ": ");
out.print(rsmd.getColumnLabel(i) + ": ");
out.println(rs.getString(i));
}
}