Eclipse: Iteration's count while Debugging a for each loop [duplicate] - java

This question already has answers here:
Is there a way to access an iteration-counter in Java's for-each loop?
(16 answers)
Closed 5 years ago.
Can we know the count of the iteration (that is whether it's the first, second, third ... iteration ) while we are stepping over the code in a for each loop, in the eclipse debugger? Eclipse must be holding a count but how to get it show it to us. Apart from the workarounds of introducing an index in the code can we utilize something in built in eclipse.

You can initiate a counter and increment it in the for loop, it should be a workaround.
You can track the variable under Eclipse console below:

Related

Does Java optimize loop checks? [duplicate]

This question already has answers here:
Java for Loop evaluation
(9 answers)
JVM option to optimize loop statements
(4 answers)
Closed 3 years ago.
if I have the following code:
int p=something
int l=somethingelse
int sum=0;
for(int i=0;i<p-l;i++)
sum+=(~i)^2+1337
can I generally assume the compiler optimizes the code so that p-l aren't recalculated every loop and is just cached since neither is changed in the loop? Or do I have to put p-l into a seperate variable if I want optimal performance?

What does the number after # in thread view in Intellij IDEA mean? [duplicate]

This question already has answers here:
While debugging java app what information is shown for a variable in a stack frame [duplicate]
(3 answers)
Closed 4 years ago.
What does 954 mean? I have checked both thread's id and hashcode(), but they don't equal 954.
Also, when using evaluate, there is also a number after #, I think they have the same meaning but still couldn't find out what's the meaning.
Interesting question. I just always took for granted that it is some id that uniquely identifies the object.
Based on that assumption it could for example be the uniqueId() returned by the Java Debugger Interface for an ObjectReference:
https://docs.oracle.com/javase/7/docs/jdk/api/jpda/jdi/
But that is really just an assumption.

What is this element and how does one use it? [duplicate]

This question already has answers here:
"loop:" in Java code. What is this, and why does it compile?
(12 answers)
Closed 7 years ago.
In this code:
search :
for (int i = 1; i <= 30; i++) {
System.out.println(i);
if (i == 20) {
break search;
}
}
What is search and how does one use it?
And wouldn't this code do the same without it?
search: is a label. You use labels with loops (break and continue) to indicate which loop is to be exited or continued.
Tutorial: https://docs.oracle.com/javase/tutorial/java/nutsandbolts/branch.html
In this case, there's only one loop. So yes I think the program would work the same without the label. However, occasionally I've seen labels used as a kind of comment to indicate what exactly is being done, and I guess that's what the coder here has done

Autocomplete ArrayList declaration [duplicate]

This question already has answers here:
IntelliJ IDEA 12 code completion without capitalisation
(2 answers)
Closed 7 years ago.
Can IntelliJ Idea autocomplete my arraylist declaration if I
entered typename with lower case?
When I type ArrayL starting with capital letter I'm getting autocompletetion instantly.
But if I start typing arraylist with lowercase I can not get autocompletetion in any way. I tried ctrl-space, ctrl-shift-space but none of them works for me.
Maybe you can check this answer. Not sure if it is exactly the same currently, since this link refers to version 12 and current is 15:
IntelliJ IDEA 12 code completion without capitalisation

Unfamiliar piece of enhanced for loop syntax [duplicate]

This question already has answers here:
"loop:" in Java code. What is this, and why does it compile?
(12 answers)
Closed 9 years ago.
I have the job of going through another's code and I'm trying to figure it all out when I came across this for loop.
//I don't understand the purpose of assetLoop
assetLoop: for (AssetObject asset : assets) {
//Some code
}
I've never seen this syntax and I can't find any reference to it anywhere through my google searches. Can anyone tell me what assetLoop: is doing? Or simply give me the name of this concept so I can do some non-mindless googling and read about it? :)
This is called a label.
It allows you to write break assetLoop from a nested loop to break out of the outer loop.
It's essentially a limited form of goto, and is rarely used.
It's a label. You can put them on any statement. break assetLoop; will break out of that loop, even if the break statement is within another for, while, do-while or switch statement. Similarly continure assetLoop; will jump to the next iteration of the loop.

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