If true the processing of the exception handlers related to an invoke statement will be aborted if the relation between the type of the thrown exception and the caught type is unknown.

If true the processing of the exception handlers related to an athrow statement will be aborted if the relation between the type of the thrown exception and the caught type is unknown.

Called by the abstract interpreter when an exception is thrown that is not (guaranteed to be) handled within the same method.

The given value, which is a value with computational type reference, is returned by the return instruction with the given pc.

The given value, which is a value with computational type double, is returned by the return instruction with the given pc.

The given value, which is a value with computational type float, is returned by the return instruction with the given pc.

Returns the field's value and/or a new NullPointerException if the given objectref represents the value null.

The given value, which is a value with computational type integer, is returned by the return instruction with the given pc.

Conversion of the given long value to a double value.

Conversion of the given long value to a float value.

Conversion of the given long value to an integer value.

The given value, which is a value with computational type long, is returned by the return instruction with the given pc.

Shift left of a long value.

Shift right of a long value.

Unsigned shift right of a long value.

Handles a monitorenter instruction.

Handles a monitorexit instruction.

Returns the project that is currently analyzed.

Sets the field's value if the given objectref is not null(in the Domain). In the latter case a NullPointerException is thrown.

Sets the field's value.

Called when a return instruction with the given pc is reached. In other words, when the method returns normally.

If true, all instructions that may raise an arithmetic exception (e.g., idiv, ldiv) should do so if it is impossible to statically determine that no exception will occur. But, if we can statically determine that the operation will raise an exception then the exception will be thrown – independently of this setting. Furthermore, if we can statically determine that no exception will be raised, no exception will be thrown. Hence, this setting only affects computations with values with incomplete information.

If true an ArrayIndexOutOfBoundsException is thrown if the index cannot be verified to be valid.

If true an ArrayStoreException is thrown if it cannot be verified that the value can be stored in the array.

If true a ClassCastException is thrown by CHECKCAST instructions if it cannot be verified that no ClassCastException will be thrown.

Throw a ClassNotFoundException if the a specific reference type is not known in the current context. The context is typically a specific Project.

Determines the behavior how method calls are handled when the exceptions that the called method may throw are unknown.

If true then monitorexit and the (XXX)return instructions will throw IllegalMonitorStateExceptions unless the analysis is able to determine that the exception is guaranteed not to be raised.

If true a NegativeArraySizeException is thrown if the index cannot be verified to be positive.

Returns true if potential NullPointerExceptions should be thrown and false if such NullPointerExceptions should be ignored. However, if the interpreter identifies a situation in which a NullPointerException is guaranteed to be thrown, it will be thrown.

Returns true if potential NullPointerExceptions should be thrown and false if such NullPointerExceptions should be ignored. However, if the interpreter identifies a situation in which a NullPointerException is guaranteed to be thrown, it will be thrown.

Returns true if potential NullPointerExceptions should be thrown and false if such NullPointerExceptions should be ignored. However, if the interpreter identifies a situation in which a NullPointerException is guaranteed to be thrown, it will be thrown. Example:

def demo(o : Object) {
     o.toString  // - If "true", a NullPointerException will ALSO be thrown;
                 //   the operation also succeeds.
                 // - If "false" the operation will "just" succeed
}

Returns true if potential NullPointerExceptions should be thrown and false if such NullPointerExceptions should be ignored. However, if the interpreter identifies a situation in which a NullPointerException is guaranteed to be thrown, it will be thrown.

If true a VM level NullPointerExceptions is thrown if the exception that is to be thrown may be null.

Represents an unknown double value.

Enables matching of DomainValues that are array values.

Represents an unspecific, unknown long value.

Extractor for IntegerRange values.

Defines a total order on reference values with a single origin by subtracting both origins.

Factory method to create a new instance of AnIntegerValue.

Creates a non-null object that represent a ArithmeticException and that has the given origin. If the ArithmeticException was created by the VM while evaluating an instruction with the program counter pc you use the method ValueOriginForImmediateVMException to translate that pc to the appropriate ValueOrigin.

Creates a non-null object that represent a ArrayIndexOutOfBoundsException and that has the given origin. If the ArrayIndexOutOfBoundsException was created by the VM while evaluating an instruction with the program counter pc you use the method ValueOriginForImmediateVMException to translate that pc to the appropriate ValueOrigin.

Creates a non-null object that represent a ArrayStoreException and that has the given origin. If the ArrayStoreException was created by the VM while evaluating an instruction with the program counter pc you use the method ValueOriginForImmediateVMException to translate that pc to the appropriate ValueOrigin.

Creates a new DomainValue that represents an array value with unknown values and where the specified type may also just be an upper type bound (unless the component type is a primitive type or an array of primitives.)

Typical Usage

This factory method is (typically) used to create a domain value that represents an array if we know nothing specific about the array. E.g., if you want to analyze a method that takes an array as a parameter.

Summary

The properties of the value are:

• Type: Upper Bound (unless the elementType is a base type)
• Null: Unknown
• Size: Unknown
• Content: Unknown

Factory method to create a representation of a boolean value with the given initial value and origin.

The domain may ignore the information about the value and the origin (origin).

Factory method to create a representation of a boolean value if we know the origin of the value.

The domain may ignore the information about the origin (origin).

Factory method to create a DomainValue that represents the given byte value and that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the value and the origin (origin).

Factory method to create a DomainValue that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the origin (origin).

Factory method to create a DomainValue that represents the given char value and that was created (explicitly or implicitly) by the instruction with the specified program counter.

Factory method to create a DomainValue that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the origin (origin).

Creates a non-null object that represent a ClassCastException and that has the given origin. If the ClassCastException was created by the VM while evaluating an instruction with the program counter pc you use the method ValueOriginForImmediateVMException to translate that pc to the appropriate ValueOrigin.

Factory method to create a DomainValue that represents a runtime value of type "Class<T>" and that was created by the instruction with the specified program counter.

This function is called by OPAL when a class constant (LDC(_W) instruction) is put on the stack.

The domain may ignore the information about the value and the origin (vo).

Summary

The properties of the domain value are:

• Initialized: Yes and the type represented by the class is the given type.
• Type: java.lang.Class<t:Type>
• Null: No

Creates the domain value that represents the constant field value.

Creates a DomainValue that represents a value with the given type and which is initialized using the JVM's default value for that type. E.g., for IntegerValues the value is set to 0. In case of a ReferenceType the value is the ReferenceValuesFactory#NullValue.

The class tag can be used to create type safe arrays or to extract the concrete type of the domain value.

val DomainReferenceValue(v) = value // of type "DomainValue"
// v is now of the type DomainReferenceValue

The class tag for the type DomainValue.

Required to generate instances of arrays in which values of type DomainValue can be stored in a type-safe manner.

Initialization

In the sub-trait or class that fixes the type of DomainValue it is necessary to implement this abstract val using:

val DomainValueTag : ClassTag[DomainValue] = implicitly

(As of Scala 2.10 it is necessary that you do not use implicit in the subclass - it will compile, but fail at runtime.)

Factory method to create a DomainValue that represents the given double value and that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the value and the origin (vo).

Factory method to create a DomainValue that was created (explicitly or implicitly) by the instruction with the specified program counter, but where we have no knowledge about the precise value.

The domain may ignore the information about the origin (vo).

Factory method to create a DomainValue with the specified origin. The origin is typically the program counter of the instruction that created this value/where the value was observed for the first time.

The domain may ignore the information about the origin (origin).

Factory method to create a DomainValue with the specified origin. The origin is typically the program counter of the instruction that created this value/where the value was observed for the first time.

The domain may ignore the information about the origin (origin).

Creates a non-null object that represent an IllegalMonitorStateException and that has the given origin. If the IllegalMonitorStateException was created by the VM while evaluating an instruction with the program counter pc you should use the method ValueOriginForImmediateVMException to translate that pc to the appropriate ValueOrigin.

Creates a domain value from the given value information that represents a properly domain value. A representation of a proper value is created even if the value information is provided for an uninitialized value.

Factory method to create a DomainValue that represents an initialized reference value of the given type and that was created (explicitly or implicitly) by the instruction with the specified program counter.

General Remarks

The given type usually identifies a class type (not an interface type) that is not abstract, but in some cases (e.g. consider java.awt.Toolkit()) it may be useful/meaningful to relax this requirement and to state that the class precisely represents the runtime type – even so the class is abstract. However, such decisions need to be made by the domain.

This method is used by the OPAL framework to create reference values that are normally internally created by the JVM (in particular exceptions such as NullPointerException and ClassCastException). However, it can generally be used to create initialized objects/arrays.

Summary

The properties of the domain value are:

• Initialized: Yes
• Type: precise (i.e., this type is not an upper bound, the type correctly models the runtime type.)
• Null: No (This value is not null.)

Factory method to create a representation of the integer constant value 0.

OPAL in particular uses this special value for performing subsequent computations against the fixed value 0 (e.g., for if_XX instructions).

(The origin (ValueOrigin) that is used is the ConstantValueOrigin to signify that this value was not created by the program.)

The domain may ignore the information about the value.

Creates a new IntegerRange value with the given bounds.

Creates a new IntegerRange value with the given bounds.

Creates a new IntegerRange value with the lower and upper bound set to the given value.

Factory method to create a DomainValue that represents the given integer value and that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the value and the origin (origin).

Factory method to create a DomainValue that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the origin (origin).

Factory method to create a DomainValue that represents the given long value and that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the value and the origin (vo).

Factory method to create a DomainValue that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the origin (vo).

The result of the merge of two incompatible values has to be reported as a MetaInformationUpdate[DomainIllegalValue].

Called by the AI framework for each load constant method handle (org.opalj.br.instructions.LoadMethodHandle) instruction to get a representation of/a DomainValue that represents the handle.

Called by the framework for each load constant method type (org.opalj.br.instructions.LoadMethodType) instruction to get a domain-specific representation of the method descriptor as a MethodType.

Creates a non-null object that represent a NegativeArraySizeException and that has the given origin. If the NegativeArraySizeException was created by the VM while evaluating an instruction with the program counter pc you use the method ValueOriginForImmediateVMException to translate that pc to the appropriate ValueOrigin.

The lengths per dimension are found in the following order: ..., count1, [count2, ...] ->

Factory method to create a new domain value that represents a newly created array (non-null) with the size determined by count that is empty.

Typical Usage

This factory method is (implicitly) used, e.g., by OPAL when a newarray instruction is found.

Summary

The properties of the value are:

• Type: Precise
• Null: No
• Size: Count
• Content: Symbol("Empty")' (i.e., default values w.r.t. to the array's component type)

Creates a new DomainValue that represents a new, uninitialized instance of an object of the given type. The object was created by the (NEW) instruction with the specified program counter.

OPAL calls this method when it evaluates newobject instructions. If the bytecode is valid a call of one of the (super) object's constructors will subsequently initialize the object.

Summary

The properties of the domain value are:

• Initialized: no (only the memory is allocated for the object)
• Type: precise (i.e., this type is not an upper bound, the type correctly models the runtime type.)
• Null: no (This value is not null.)

Represents a non-null reference value with the given type as an upper type bound.

The domain may ignore the information about the value and the origin (vo).

Summary

The properties of the domain value are:

• Initialized: Yes (the constructor was called)
• Type: Upper Bound
• Null: No (This value is not null.)

Creates a non-null object that represent a NullPointerException and that has the given origin. If the NullPointerException was created by the VM while evaluating an instruction with the program counter pc you should use the method ValueOriginForImmediateVMException to translate that pc to the appropriate ValueOrigin.

Factory method to create a DomainValue that represents value null and and that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the value and the origin (pc).

Summary

The properties of the domain value are:

• Initialized: N/A
• Type: Null
• Null: Yes

Factory method to create a DomainValue that represents either an class-/interface value that has the given types as an upper bound or the value null. However, the information whether the value is null or not is not available. Furthermore, the type may also just be an upper bound and it is not known if the value is properly initialized.

Summary

The properties of the domain value are:

• Initialized: Yes (An Object with multiple bounds can only exist due to a merge, in this case, the objects must have been initialized beforehand or the value is not used at all and actually represents a dead variable.)
• Type: Upper Bound
• Null: Unknown
• Content: Unknown

Factory method to create a DomainValue that represents either an class-/interface value that has the given type or the value null. However, the information whether the value is null or not is not available. Furthermore, the type may also just be an upper bound and it is not known if the value is properly initialized.

Summary

The properties of the domain value are:

• Initialized: Unknown (I.e., it is not guaranteed that the constructor was called; unless NewObject was overridden and returns DomainValues that are distinguishable!)
• Type: Upper Bound
• Null: Unknown
• Content: Unknown

Creates an update object that characterizes a reference id update.

Basically, just a wrapper for a MetaInformationUpdate; the purpose is to better communicate the underlying purpose.

Factory method to create a DomainValue that represents either a reference value that has the given type and is initialized or the value null. However, the information whether the value is null or not is not available. Furthermore, the type may also just be an upper bound.

The domain may ignore the information about the value and the origin, but it has to remain possible for the domain to identify the component type of an array.

Summary

The properties of the domain value are:

• Initialized: Yes (if non-null the constructor was called/the array was initialized)
• Type: Upper Bound
• Null: Unknown
• Content: Unknown

Factory method to create an instance of a ReturnAddressValue.

Factory method to create a DomainValue that represents the given short value and that was created (explicitly or implicitly) by the instruction with the specified program counter.

Factory method to create a DomainValue that was created (explicitly or implicitly) by the instruction with the specified program counter.

The domain may ignore the information about the origin (origin).

Factory method to create a DomainValue that represents the given string value and that was created by the instruction with the specified program counter.

This function is called by OPAL-AI when a string constant (LDC(_W) instruction) is put on the stack.

The domain may ignore the information about the value and the origin (vo).

Summary

The properties of the domain value are:

• Initialized: Yes and the String's value is the given value. The string may be empty (""), but it is never null.
• Type: java.lang.String
• Null: No

The result of merging two values should never be reported as a StructuralUpdate if the computed value is an IllegalValue. The JVM semantics guarantee that the value will not be used and, hence, continuing the interpretation is meaningless.

The singleton instance of the IllegalValue.

The singleton instance of ReturnAddressValues

Creates a non-null object that represent a Throwable object and that has the given origin. If the Throwable was created by the VM while evaluating an instruction with the program counter pc you should use the method ValueOriginForImmediateVMException to translate that pc to the appropriate ValueOrigin.

Factory method to create domain values with a specific type. I.e., values for which we have some type information but no precise value or source information. However, the value is guaranteed to be null or properly initialized.

For example, if valueType is a reference type it may be possible that the actual value is null, but such knowledge is not available.

The framework uses this method when a method is to be analyzed, but no parameter values are given and initial values need to be generated. This method is not used elsewhere by the framework.

Creates a new DomainValue that represents the this value of a constructor before the super constructor is called. Hence, the value origin is necessarily always -1.

OPAL calls this method when it creates the initial locals for constructors.

Summary

The properties of the domain value are:

• Initialized: no (only the memory is allocated for the object)
• Type: upper bound
• Null: no (This value is not null.)

Called by the abstract interpreter when the abstract interpretation of a method has ended. The abstract interpretation of a method ends if either the fixpoint is reached or the interpretation was aborted.

By default this method does nothing.

Domains that override this method are expected to also call super.abstractInterpretationEnded(aiResult).

Classes overriding this method generally have to call it!

This methods is called after the evaluation of the instruction with the given pc with respect to targetPC, but before the values are propagated (joined) and before it is checked whether the interpretation needs to be continued. I.e., if the operands (newOperands) or locals (newLocals) are further refined then the refined operands and locals are joined (if necessary).

Returns the array's length or throws a NullPointerException if the given reference is null.

Loads the value stored in the array at the given index or throws an exception (NullPointerException or IndexOutOfBoundsException).

Stores the given value in the array at the given index or throws an exception (NullPointerException, ArrayStoreException or IndexOutOfBoundsException).

Returns the given value as a DomainReferenceValue. Basically just performs a type cast and is intended to be used to communicate that the value has to be a reference value (if the underlying byte code is valid.)

This method is called immediately before a join operation with regard to the specified pc is performed.

Returns the project's class hierarchy.

Computes the effective upper-type bound which is the (single) final type in the utb if it contains one. In this case the other types have to be in a super-/subtype relation and were added "just" as a result of explicit CHECKCAST instructions.

Called by the framework after evaluating the instruction with the given pc. I.e., the state of all potential successor instructions was updated and the flow method was called – potentially multiple times – accordingly.

By default this method does nothing.