Analysis Details

Never Confuse the Inmutability of a Reference with that of the Referenced Object

es.uniovi.reflection.analyses.cmu.obj50

It is checked that the state of objects pointed by final references is not mutated. We exclude assignments to fields inside constructors (or methods only called by constructors) since we understood them as initialization, not mutations.

Computational Reflection Research Group

12-03-2025 17:14

Programmer Misconceptions

Variable Declaration

MATCH (declaration:VARIABLE_DEC{isFinal:true})-[r:STATE_MODIFIED_BY|STATE_MAY_BE_MODIFIED_BY]->(mutatorExpr:EXPRESSION)
WITH declaration, mutatorExpr, es.uniovi.reflection.codeanalysis.functions.getEnclCallableFromExpr(mutatorExpr) as method, r
MATCH (method)<-[:DECLARES_FIELD|DECLARES_METHOD|DECLARES_CONSTRUCTOR|TYPE_STATIC_INIT]-(exprEnclClass)
WHERE NOT declaration:ATTR_DEC OR r.isOwnAccess=FALSE OR NOT method.isInitializer
WITH declaration, mutatorExpr, exprEnclClass, es.uniovi.reflection.codeanalysis.functions.getEnclosingType(declaration) as decEncType
MATCH (decEncType)<-[:DECLARES_TYPE|HAS_NESTED_TYPE]->(cu:ORDINARY_CU)
WITH cu, declaration, decEncType, COLLECT(LAST(LABELS(mutatorExpr)) + ', line ' + mutatorExpr.lineNumber + ', column ' + mutatorExpr.column + ', class ' + exprEnclClass.fullyQualifiedName) as mutatorsMessage
RETURN '{"node":"VARIABLE_DEC '+declaration.actualType+' '+declaration.name+'","line":"'+declaration.lineNumber+'","column":"'+declaration.column+'","rule":"CMU-OBJ50","location":"'+cu.fileName+'","message":" Declaration with name '+declaration.name+'( in line '+declaration.lineNumber+', class '+decEncType.fullyQualifiedName+') is not actually final, only the reference. Concretely, '+declaration.name+' may be mutated in '+ REDUCE(seed = mutatorsMessage[0], x IN mutatorsMessage[1..] | seed+','+x)+'."}'