Language server reports OOM for Java heap space while switching local git branch

Use VS Code to develop eclipse.jdt.ls itself, and switch local branch to a remote PR branch, language server reports OOM exception.

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:12.066
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.core 4 4 2022-07-19 13:28:25.648
!MESSAGE Background Indexer Crash Recovery
!STACK 0
java.lang.OutOfMemoryError: Java heap space
	at org.eclipse.jdt.internal.compiler.util.HashtableOfObject.<init>(HashtableOfObject.java:56)
	at org.eclipse.jdt.internal.compiler.util.HashtableOfObject.rehash(HashtableOfObject.java:184)
	at org.eclipse.jdt.internal.compiler.util.HashtableOfObject.putUnsafely(HashtableOfObject.java:157)
	at org.eclipse.jdt.internal.core.index.DiskIndex.copyQueryResults(DiskIndex.java:383)
	at org.eclipse.jdt.internal.core.index.DiskIndex.mergeWith(DiskIndex.java:570)
	at org.eclipse.jdt.internal.core.index.Index.save(Index.java:230)
	at org.eclipse.jdt.internal.core.search.indexing.IndexManager.saveIndex(IndexManager.java:1150)
	at org.eclipse.jdt.internal.core.search.indexing.AddJrtToIndex.execute(AddJrtToIndex.java:274)
	at org.eclipse.jdt.internal.core.search.processing.JobManager.run(JobManager.java:445)
	at java.base/java.lang.Thread.run(Unknown Source)

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:30.506
!MESSAGE >> workspace/executeCommand vscode.java.test.findTestTypesAndMethods

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:30.508
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:33.420
!MESSAGE >> workspace/executeCommand vscode.java.test.findTestTypesAndMethods

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:33.423
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:33.652
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:33.945
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:33.964
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:33.997
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.145
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.269
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.339
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.444
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.592
!MESSAGE >> workspace/executeCommand vscode.java.test.findTestTypesAndMethods

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.596
!MESSAGE >> workspace/didChangeWatchedFiles 

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.664
!MESSAGE >> workspace/executeCommand vscode.java.test.findTestTypesAndMethods

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.665
!MESSAGE >> document/codeAction

!ENTRY org.eclipse.jdt.ls.core 1 0 2022-07-19 13:28:34.668
!MESSAGE >> document/codeAction

Tái hiện sự cố trong VS Code bằng cách chuyển branch cục bộ sang một branch PR từ xa, sau đó kiểm tra hoạt động của workspace/didChangeWatchedFiles và stack trace lập chỉ mục JDT được báo cáo thông qua DiskIndex, Index và AddJrtToIndex. Được xem là hoàn tất khi việc chuyển branch không còn gây ra lỗi Java heap space; issue không chỉ định tệp kiểm thử hoặc tệp mã nguồn nào cần chạy hay chỉnh sửa.