/** Check null-ness of 'var' against a possible null annotation */
protected int checkAssignmentAgainstNullAnnotation(
BlockScope currentScope,
FlowContext flowContext,
VariableBinding var,
int nullStatus,
Expression expression,
TypeBinding providedType) {
int severity = 0;
if ((var.tagBits & TagBits.AnnotationNonNull) != 0 && nullStatus != FlowInfo.NON_NULL) {
flowContext.recordNullityMismatch(
currentScope, expression, providedType, var.type, nullStatus);
return FlowInfo.NON_NULL;
} else if ((severity = findNullTypeAnnotationMismatch(var.type, providedType)) > 0) {
currentScope
.problemReporter()
.nullityMismatchingTypeAnnotation(
expression, providedType, var.type, severity == 1, currentScope.environment());
} else if ((var.tagBits & TagBits.AnnotationNullable) != 0
&& nullStatus == FlowInfo.UNKNOWN) { // provided a legacy type?
return FlowInfo.POTENTIALLY_NULL; // -> use more specific info from the annotation
}
return nullStatus;
}
/** Analysing arguments of MessageSend, ExplicitConstructorCall, AllocationExpression. */
protected void analyseArguments(
BlockScope currentScope,
FlowContext flowContext,
FlowInfo flowInfo,
MethodBinding methodBinding,
Expression[] arguments) {
// compare actual null-status against parameter annotations of the called method:
if (arguments != null) {
CompilerOptions compilerOptions = currentScope.compilerOptions();
boolean considerTypeAnnotations =
compilerOptions.sourceLevel >= ClassFileConstants.JDK1_8
&& compilerOptions.isAnnotationBasedNullAnalysisEnabled;
boolean hasJDK15NullAnnotations = methodBinding.parameterNonNullness != null;
int numParamsToCheck = methodBinding.parameters.length;
if (considerTypeAnnotations || hasJDK15NullAnnotations) {
// check if varargs need special treatment:
boolean passThrough = false;
if (methodBinding.isVarargs()) {
int varArgPos = numParamsToCheck - 1;
// this if-block essentially copied from generateArguments(..):
if (numParamsToCheck == arguments.length) {
TypeBinding varArgsType = methodBinding.parameters[varArgPos];
TypeBinding lastType = arguments[varArgPos].resolvedType;
if (lastType == TypeBinding.NULL
|| (varArgsType.dimensions() == lastType.dimensions()
&& lastType.isCompatibleWith(varArgsType)))
passThrough = true; // pass directly as-is
}
if (!passThrough)
numParamsToCheck--; // with non-passthrough varargs last param is fed from individual
// args -> don't check
}
}
if (considerTypeAnnotations) {
for (int i = 0; i < numParamsToCheck; i++) {
TypeBinding expectedType = methodBinding.parameters[i];
Expression argument = arguments[i];
// prefer check based on type annotations:
int severity = findNullTypeAnnotationMismatch(expectedType, argument.resolvedType);
if (severity > 0) {
// immediate reporting:
currentScope
.problemReporter()
.nullityMismatchingTypeAnnotation(
argument,
argument.resolvedType,
expectedType,
severity == 1,
currentScope.environment());
// next check flow-based null status against null JDK15-style annotations:
} else if (hasJDK15NullAnnotations
&& methodBinding.parameterNonNullness[i] == Boolean.TRUE) {
int nullStatus =
argument.nullStatus(
flowInfo,
flowContext); // slight loss of precision: should also use the null info from
// the receiver.
if (nullStatus != FlowInfo.NON_NULL) // if required non-null is not provided
flowContext.recordNullityMismatch(
currentScope, argument, argument.resolvedType, expectedType, nullStatus);
}
}
} else if (hasJDK15NullAnnotations) {
for (int i = 0; i < numParamsToCheck; i++) {
if (methodBinding.parameterNonNullness[i] == Boolean.TRUE) {
TypeBinding expectedType = methodBinding.parameters[i];
Expression argument = arguments[i];
int nullStatus =
argument.nullStatus(
flowInfo,
flowContext); // slight loss of precision: should also use the null info from
// the receiver.
if (nullStatus != FlowInfo.NON_NULL) // if required non-null is not provided
flowContext.recordNullityMismatch(
currentScope, argument, argument.resolvedType, expectedType, nullStatus);
}
}
}
}
}