Package org.checkerframework.dataflow.util

Class PurityChecker

java.lang.Object

org.checkerframework.dataflow.util.PurityChecker

public final class PurityChecker
extends Object

A visitor that determines the purity (as defined by SideEffectFree, Deterministic, and Pure) of a statement or expression. The entry point is method checkPurity(com.sun.source.util.TreePath, org.checkerframework.javacutil.AnnotationProvider, boolean, boolean, boolean).

This class does not check SideEffectsOnly, which is the other purity annotation. Verifying @SideEffectsOnly requires parsing the Java expressions in the annotation and viewpoint-adapting them at each call site, which this module cannot do. org.checkerframework.common.basetype.DisallowedSideEffects, which BaseTypeVisitor calls, checks @SideEffectsOnly.

See Also:

• SideEffectFree
• Deterministic
• Pure

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	PurityChecker.PurityCheckerHelper	Helper class to keep PurityChecker's interface clean.
static class	PurityChecker.PurityResult	Result of the PurityChecker.

Method Summary

Modifier and Type	Method	Description
static PurityChecker.PurityResult	checkPurity(TreePath statement, AnnotationProvider annoProvider, boolean assumeSideEffectFree, boolean assumeDeterministic, boolean assumePureGetters)	Compute whether the given statement is side-effect-free, deterministic, or both.
static PurityChecker.PurityResult	checkPurity(List<TreePath> statements, AnnotationProvider annoProvider, boolean assumeSideEffectFree, boolean assumeDeterministic, boolean assumePureGetters)	Compute whether the given statements, taken together, are side-effect-free, deterministic, or both.

Methods inherited from class java.lang.Object

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

Method Details

checkPurity

public static PurityChecker.PurityResult checkPurity(TreePath statement,
 AnnotationProvider annoProvider,
 boolean assumeSideEffectFree,
 boolean assumeDeterministic,
 boolean assumePureGetters)

Compute whether the given statement is side-effect-free, deterministic, or both. Returns a result that can be queried.

Parameters:

statement - the statement to check

annoProvider - the annotation provider

assumeSideEffectFree - true if all methods should be assumed to be @SideEffectFree

assumeDeterministic - true if all methods should be assumed to be @Deterministic

assumePureGetters - true if all getter methods should be assumed to be @Pure

Returns:

information about whether the given statement is side-effect-free, deterministic, or both

checkPurity

public static PurityChecker.PurityResult checkPurity(List<TreePath> statements,
 AnnotationProvider annoProvider,
 boolean assumeSideEffectFree,
 boolean assumeDeterministic,
 boolean assumePureGetters)

Compute whether the given statements, taken together, are side-effect-free, deterministic, or both. Returns a result that can be queried.

Use this rather than calling checkPurity(TreePath, AnnotationProvider, boolean, boolean, boolean) once per statement, for code that runs as a unit but is not contiguous in the source code: a constructor together with the instance initializers that run as part of it, for example.

Parameters:

statements - the statements to check

annoProvider - the annotation provider

assumeSideEffectFree - true if all methods should be assumed to be @SideEffectFree

assumeDeterministic - true if all methods should be assumed to be @Deterministic

assumePureGetters - true if all getter methods should be assumed to be @Pure

Returns:

information about whether the given statements are side-effect-free, deterministic, or both