java.lang.Object
- java.lang.Enum<TypeOps.Convertibility>
- - net.sourceforge.pmd.lang.java.types.TypeOps.Convertibility

All Implemented Interfaces:

Serializable, Comparable<TypeOps.Convertibility>

Enclosing class:

TypeOps
```
public static enum TypeOps.Convertibility
extends Enum<TypeOps.Convertibility>
```
A result for a convertibility check. This is a tiny generalization of a subtyping check.
Primitive types are implicitly convertible to each other by widening primitive conversion. For reference types, subtyping implies convertibility (the conversion is technically called "widening reference conversion"). You can check those cases using: t.isConvertibleTo(s).bySubtyping()
Unchecked conversion may go backwards from subtyping. For example, List<String> is a subtype of the raw type List, and as such is convertible to it by reference widening. But List may be "coerced" to List<String> with an unchecked warning: t.isConvertibleTo(s).withUncheckedWarning()
If the parameterized type only has wildcard type arguments, then the conversion produces no warning. t.isConvertibleTo(s) == UNCHECKED_NO_WARNING
Two types may be unconvertible: t.isConvertibleTo(s).never()
the negation of which being t.isConvertibleTo(s).somehow()
Note that this does not check for boxing or unboxing conversions, nor for narrowing conversions, which may happen through casts.

Enum Constant Summary

Enum Constants
Enum Constant	Description
`NEVER`	T is never implicitly convertible to S.
`SUBTYPING`	T is a subtype of S (`T <: S`).
`UNCHECKED_NO_WARNING`	`T <: \|S\|` and `T </: S`, but S is parameterized with only unbounded wildcards.
`UNCHECKED_WARNING`	T is not a subtype of S, but every time T is used in a context where an S is expected, unchecked conversion converts the T to an S with a mandated warning.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`bySubtyping()`	True if this is `SUBTYPING`.
`boolean`	`never()`	Returns true if this is `NEVER`.
`boolean`	`somehow()`	Returns true if this is anything but `NEVER`.
`static TypeOps.Convertibility`	`valueOf(String name)`	Returns the enum constant of this type with the specified name.
`static TypeOps.Convertibility[]`	`values()`	Returns an array containing the constants of this enum type, in the order they are declared.
`boolean`	`withoutWarnings()`	True if this is `SUBTYPING` or `UNCHECKED_NO_WARNING`.
`boolean`	`withUncheckedWarning()`	True if this is `UNCHECKED_WARNING`.

Methods inherited from class java.lang.Enum
clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait

- Enum Constant Detail
  - NEVER
```
public static final TypeOps.Convertibility NEVER
```
    T is never implicitly convertible to S.
  - UNCHECKED_WARNING
```
public static final TypeOps.Convertibility UNCHECKED_WARNING
```
    T is not a subtype of S, but every time T is used in a context where an S is expected, unchecked conversion converts the T to an S with a mandated warning. For example the raw type Class is convertible to Class<String> with an unchecked warning.
  - UNCHECKED_NO_WARNING
```
public static final TypeOps.Convertibility UNCHECKED_NO_WARNING
```
    T <: |S| and T </: S, but S is parameterized with only unbounded wildcards. This is a special case of unchecked conversion that produces no warning. We keep it distinct from subtyping to help some algorithms that require subtyping to be a partial order.
    For example, List<String> is a subtype of the raw Collection, not a subtype of Collection<?>, but it is still convertible without warning.
  - SUBTYPING
```
public static final TypeOps.Convertibility SUBTYPING
```
    T is a subtype of S (T <: S). In particular, any type is a subtype of itself (T <: T).
    For example, int can be widened to long, so we consider int <: long.
- Method Detail
  - values
```
public static TypeOps.Convertibility[] values()
```
    Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:
    for (TypeOps.Convertibility c : TypeOps.Convertibility.values()) System.out.println(c);
    Returns:
    
    an array containing the constants of this enum type, in the order they are declared
  - valueOf
```
public static TypeOps.Convertibility valueOf(String name)
```
    Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
    
    Parameters:
    
    name - the name of the enum constant to be returned.
    
    Returns:
    
    the enum constant with the specified name
    
    Throws:
    
    IllegalArgumentException - if this enum type has no constant with the specified name
    
    NullPointerException - if the argument is null
  - never
```
public boolean never()
```
    Returns true if this is NEVER.
  - somehow
```
public boolean somehow()
```
    Returns true if this is anything but NEVER.
  - bySubtyping
```
public boolean bySubtyping()
```
    True if this is SUBTYPING.
  - withUncheckedWarning
```
public boolean withUncheckedWarning()
```
    True if this is UNCHECKED_WARNING.
  - withoutWarnings
```
public boolean withoutWarnings()
```
    True if this is SUBTYPING or UNCHECKED_NO_WARNING.

Enum TypeOps.Convertibility

Enum Constant Summary

Method Summary

Methods inherited from class java.lang.Enum

Methods inherited from class java.lang.Object

Enum Constant Detail

NEVER

UNCHECKED_WARNING

UNCHECKED_NO_WARNING

SUBTYPING

Method Detail

values

valueOf

never

somehow

bySubtyping

withUncheckedWarning

withoutWarnings