Package com.intellij.util

Class AstLoadingFilter

java.lang.Object

com.intellij.util.AstLoadingFilter

public class AstLoadingFilter
extends java.lang.Object

Enforces tree loading policies.

For example it's very slow to load AST for all shown files when updating Project View nodes, or loading other files when current file is being highlighted.

To prevent loading in the current thread disallowTreeLoading(com.intellij.util.ThrowableRunnable<E>) should be used.
In this case the exception will be thrown when some code unexpectedly tries to load the tree, and then there are two options:

• examine the stack trace, fix the code, so tree loading won't occur anymore, e.g. data will be taken from stubs, and cover it with a test. It is highly preferable to fix the code, which gains a speed up.
• force allow tree loading by wrapping troublesome operation into forceAllowTreeLoading(com.intellij.psi.PsiFile, com.intellij.util.ThrowableRunnable<E>). In this case there are no performance gains, but later it will be possible to examine all bottlenecks by finding usages of forceAllowTreeLoading(com.intellij.psi.PsiFile, com.intellij.util.ThrowableRunnable<E>)

Example:

 disallowTreeLoading {
   // some deep trace
   ...
   doSomeOperation {
     // access file tree, exception is thrown
   }
   forceAllowTreeLoading(file) {
     doSomeOperation {
       // access file tree, no exception is thrown
     }
     doAnotherOperation {
       // access another file tree, exception is thrown
     }
   }
   forceAllowTreeLoading(file) {
     disallowTreeLoading {
       doSomeOperation {
         // nested disallowing has no effect in any case
         // access file tree, no exception is thrown, access is still allowed for file
       }
     }
   }
 }
 

Note that tree access won't result in an exception when the tree was already loaded.

Method Summary

Modifier and Type	Method and Description
static void	assertTreeLoadingAllowed(VirtualFile file)
static <T,E extends java.lang.Throwable> T	disallowTreeLoading(ThrowableComputable<? extends T,E> computable)
static <T,E extends java.lang.Throwable> T	disallowTreeLoading(ThrowableComputable<? extends T,E> computable, java.util.function.Supplier<java.lang.String> debugInfo)
static <E extends java.lang.Throwable> void	disallowTreeLoading(ThrowableRunnable<E> runnable)
static <T,E extends java.lang.Throwable> T	forceAllowTreeLoading(PsiFile psiFile, ThrowableComputable<? extends T,E> computable)
static <E extends java.lang.Throwable> void	forceAllowTreeLoading(PsiFile psiFile, ThrowableRunnable<E> runnable)
static <T,E extends java.lang.Throwable> T	forceAllowTreeLoading(VirtualFile virtualFile, ThrowableComputable<? extends T,E> computable)
static <E extends java.lang.Throwable> void	forceAllowTreeLoading(VirtualFile virtualFile, ThrowableRunnable<E> runnable)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

assertTreeLoadingAllowed

public static void assertTreeLoadingAllowed(VirtualFile file)

disallowTreeLoading

public static <E extends java.lang.Throwable> void disallowTreeLoading(ThrowableRunnable<E> runnable)
                                                                throws E extends java.lang.Throwable

Throws:

E extends java.lang.Throwable

disallowTreeLoading

public static <T,E extends java.lang.Throwable> T disallowTreeLoading(ThrowableComputable<? extends T,E> computable)
                                                               throws E extends java.lang.Throwable

Throws:

E extends java.lang.Throwable

disallowTreeLoading

public static <T,E extends java.lang.Throwable> T disallowTreeLoading(ThrowableComputable<? extends T,E> computable,
                                                                      java.util.function.Supplier<java.lang.String> debugInfo)
                                                               throws E extends java.lang.Throwable

Throws:

E extends java.lang.Throwable

forceAllowTreeLoading

public static <E extends java.lang.Throwable> void forceAllowTreeLoading(PsiFile psiFile,
                                                                         ThrowableRunnable<E> runnable)
                                                                  throws E extends java.lang.Throwable

Throws:

E extends java.lang.Throwable

forceAllowTreeLoading

public static <E extends java.lang.Throwable> void forceAllowTreeLoading(VirtualFile virtualFile,
                                                                         ThrowableRunnable<E> runnable)
                                                                  throws E extends java.lang.Throwable

Throws:

E extends java.lang.Throwable

forceAllowTreeLoading

public static <T,E extends java.lang.Throwable> T forceAllowTreeLoading(PsiFile psiFile,
                                                                        ThrowableComputable<? extends T,E> computable)
                                                                 throws E extends java.lang.Throwable

Throws:

E extends java.lang.Throwable

forceAllowTreeLoading

public static <T,E extends java.lang.Throwable> T forceAllowTreeLoading(VirtualFile virtualFile,
                                                                        ThrowableComputable<? extends T,E> computable)
                                                                 throws E extends java.lang.Throwable

Throws:

E extends java.lang.Throwable