Some of my variables are huge (include tables with so many rows). When I try to see the variables via variables view in Eclipse, it shows a part of it, not the all. So, I need to use system.out.println("myVariable"); to see, what my variable contains, and this not an effective way.
Is there a way to get over this? Or do you offer a better solution than sys.out.println?
The best I would suggest is to use the display view:
menu -> window -> show view -> debug ->display
inside the display view, type the variable name, right click and select display. Still if short, use the sysout statement there, and again, right click and select display.
Hope this helps.
In Variables window we have grid with list of variables and a field with variable signification below. Right click on this field => "Max Lenght ..."
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I am trying to view the instance variables values of the Arraylist in eclipse in debug mode but apart from the values in the list am unable to view variables like elementData or modCount that are part of the arraylist. I have tried using Watch, Display option as well but to no avail. Below is my screenshot after setting the breakpoint and triggering the program run:
Below is the screenshot that I found in one of the websites where the instance variables like elementData,modCount and size are visible:
In the current version (Oxygen.3) the default formatter for Collection shows only the members of the collection as an array. I'm not sure when the more detailed formatter was removed, but you can easily create a logical structure formatter.
Right click on the variable in the Variables tab and select Show Logical Structure/Edit Logical Structure
Your view will have the Collection entry hilighted, and won't contain the ArrayList entry I just created.
Add a new entry:
Provide the class name you want to format, and a description. Select List of Variables and then add the variables you want to display, providing a code snippet for each one. The code snippet executes as a method of the class.
End result:
In oxygen, "Show Logical Structure" is enabled by default. All you have to do is click on it to disable it.
[Image taken from eclipse.org]
In some instances that I cannot view variables, like in your case, I would suggest using Expression tab and add new expression. To load expression tab on Eclipse IDE, click on Window > Show View > Expression. Set breakpoint, hit debug, then expression tab should load arrNames and you can expand to view properties and data.
Go to Window->show view->expressions then in Expressions window go to variables tab
there you will see your variables right click on any one of them you will see Show logical structure.
Untick the Array option from there and debug again you will see elementData,modCount and size varibles.click here for image
While debugging Java code, Strings in the views "Variables" and "Expressions" show up only till a certain length, after which Eclipse shows "..."
Is there any way to inspect the entire string? (This eases the pain of adding logging statements for debugging everywhere)
In the Variables view you can right click on Details pane (the section where the string content is displayed) and select "Max Length..." popup menu. The same length applies to expression inspector popup and few other places.
In the Variables view you right-click on the variable and select Change value. If your variable is huge you have to wait a few minutes (in this case Eclipse doesn't respond to commands) but in the end Eclipse will show your variable entirely.
If you have a really long string, I use a different strategy: dump it to a file. I have a snippet of code I use in the Display view, which is evaluated to dump the data to a file. I use Commons IO, but you can do it with JDK only methods.
org.apache.commons.io.FileUtils.writeStringToFile(new java.io.File("<filename>"), <expression to evaluate>);
Naturally, you will need the Commons IO JAR in your classpath for that to work. If you don't, resort to JDK work.
The best way to view a String value from eclipse debug view is as below.
1) Switch to debug view in Eclipse
2) Select the desired variable in variable pane.
3) Right click on display area of variable pane where value is shown and click on Max Length. Enter the maximum char value in Configure Details Pane .
4) Cheers
When debugger reaches the point where you want the String value, just type a sysOut statement
System.out.println("The value is : \n " + query);
Select the above the statement, right click-> Execute
It will print the value on the console
For javascript based debugging on eclipse, "change value" method and "Max length" method both failed for me, adding the required object to watch(Expressions) and then Right Clicking the watched expression to select "Load Full Value" is the only solution that works for me, but even this inserts unwanted "\n" in the output.
Note - "Max length" must be set for the "Load Full Value" to work as it loads values till max length(default in eclipse is 10000). Refer above answer to see how to set Max length.
There is no "maxLength" in Eclipse Mars. And, the "change value" only works with "Variables", not "Expressions", so none of above works for me.
And, the expression are cut in the middle, not at the end. I guess they changed the default behaviour.
The only thing working for me, is to expand the expression name column's width, and click the expression to select it all to see the full length content.
Nothing from the above worked for me, moreover, some user interface elements in my Eclipse can not be found as described. I'm using STS 4.3.1.
The value I needed was really big, it is part of a huge JSON request. Workaround is to use an expression in Eclipse Debug Shell console and to output the substring of the whole value. Since you can see the partial value, inspect it and use the last few literals as the position to output the next chunk of the string. Repeat this approach until get what you need:
String result = new String(reallyBigByteArrayValue, "UTF-8");
result.substring(result.indexOf("some-unique-text"));
In Eclipse IDE 2020-09 it's "Pretty print to console" on right click.
From the console the copying is possible at full length.
Not quite sure whether I'm using the right terminology here, but Netbeans has a very nice feature where e.g. if you start typing for it will offer to write a code fragment looping over an array or list, basing it on the name and type of an array or list variable actually in scope.
If more than one such variable is in scope it will guess, sometimes correctly and sometimes not.
Is there a way to aim this feature at the correct array/list variable?
You can do that like this:
Type fore and press TAB. This will generate the for each loop.
The loop variable is selected. Press TAB again to select the list variable.
Finally, press CTRL+SPACE, select a different list variable, and press ENTER.
(Tested with Netbeans 8.0)
In netbeans terminology, it is called code templates (many editors call it code snippets). You can customize them also by going to tools > options > editor and select required language from the dropdow.
Is it possible to evaluate a expression in Eclipse similar to IntelliJ. Where you can dynamically type code and the result will be displayed during debug?. I know it does something similar "Display" but you need to highlight code that has been written (so you cant write any new code unless you re-compile).
Perhaps there are plugins that i could use?. I have just started using eclipse
There is a Display view as well that can do exactly what you want. Go to Window > Show view > Display (or Other... if the Display view is not there. In the Display view, you can type any code you want during debug (content assist is available). The current objects and variables are also available to use. After you wrote your code, you have to highlight it, right click and select Execute or hit CTRL-U. You may play around with the other possible actions as well.
Besides that, you can also write in the source code during debug and evaluate it using Display as you mentioned, if you have the source for the class you are debugging.
1 - Type your expression inside a method that you are debugging
2 - Select that code
3 - Press CTRL + SHIFT + I
4 - Eclipse will evaluate your expression and show the results in a floating window
You can change variable values on the fly using the Debug perspective.
The top right corner of Eclipse should have the variables view from which you can select a variable name and change its value. You can also set conditional breakpoints by selecting the breakpoints view in the top right corner of Eclipse. Right-click on the breakpoint and select breakpoint properties. Check the conditional checkbox and write an expression that only when it evaluates as true does the program suspend during Debugging.
Change Variable Values during Debug
Conditional Breakpoints
Although Display View works; There are two ways else to evaluate an expression.
In the context of the debugging session, we can write and run custom code to evaluate possibilities. This is done in the Debug Shell. For example, if we need to cross-check the correctness of the sqrt functionality, we could do it in the Debug Shell. On the code, Right-click -> Inspect to see the value.
You can select an expression then open Context Menu -> Inspect or press CTRL + Shift + I, during debugging, the result will be displayed.
Select any expression in your code. Then right-click and select "Display" (or press the associated key-combination).
For completely new expressions, use the Display view. It's like a scrapbook for expressions. If the Display view is not visible, select Window > Show view > Display to add it. Then type any expression in the view, and do the same thing as for expressions in your code: select the expression, right-click and select "Display".
For expressions that you want to always see the value of, every time execution is halted, use the Expressions view instead.
is it possible, in Eclipse, to mark certain lines with Shortcuts and be able to quickly jump to those lines?
Example: Let's say I have maintenanceHeavyMethod() at line 120 in my class, gameLoop() at line 800 and some listener at line 1460.
I'd like to f.ex. press CTRL+SHIFT+1, 2, 3 etc. to mark those positions, and then use f.ex. CTRL+1, 2, 3 to immediately jump to them. I don't like split-screens etc, but I need to jump around when writing.
Is there such a feature?
I'm using latest Eclipse to write Java-programs.
You can add Bookmarks in your code. Select the code fragment you want to bookmark and then go to Edit > Add Bookmark... (also possible via the menu available with a right-click in the left hand column of the editor, like breakpoints).
Then, add the Bookmarks view. Select Window > Show View > Other... > Bookmarks and you'll get something like this:
Sadly, I don't think you can bind a shortcut to a particular bookmark.
Just in case, the shortcut to jump to a particular line is CTRL+L.
That would be best taken care by mylyn:
Define a task with this three method, and you will be to see only those 3 in the package explorer view
To jump to a particular method, I use ctrl+o and then start typing the method. If you're a proficient typist, this shouldn't take any longer; keep in mind that you only have to start typing the name of the method.
Unfortunately this isn't a proper solution for jumping to a line of code within a method.
You can jump to methods by using the outline view. Outline view shows all the Methods, Fields, and Inner-Classes (and their methods and fields and inner-classes...etc) of the source file you currently have open. I personally prefer this method, unless I have a stacktrace and know which line I want to jump to, in which case I use ctrl+L.