It occasionally appears during debugging: Eclipse unable to install breakpoint in XXX

Situation 1:

Just clear all the breakpoints, because the breakpoints are on the comments

Breakpoint window: remove all breakpoints

Then, you can debug the code that needs to be debugged by setting a breakpoint again

Case 2:

Solution:
Step 1 check: Project – > Attribute – > Java compiler – > Class file generation – > Add line number attribute to generated class file (used by debugger) – > Check
project — > Properties—-> java Compiler—-> Classfile generation
select the check box below, click apply, and then click OK

if the problem is not solved, replace the default JRE by referring to the following method
Step 2:
replace the JRE running in the current file, which is provided by sun, instead of the JRE provided by eclipse itself
window — > preferences—-> java—-> Installed JREs—> Non EC JRE