Interface Field

All Superinterfaces:: Accessible, Comparable<Field>, Mirror, TypeComponent

public interface Field extends TypeComponent, Comparable<Field>

A class or instance variable in the target VM. See TypeComponent for general information about Field and Method mirrors.

Since:

1.3

See Also:

Method Summary

Modifier and Type	Method	Description
`boolean`	`equals(Object obj)`	Compares the specified Object with this field for equality.
`int`	`hashCode()`	Returns the hash code value for this Field.
`boolean`	`isEnumConstant()`	Determine if this is a field that represents an enum constant.
`boolean`	`isTransient()`	Determine if this is a transient field.
`boolean`	`isVolatile()`	Determine if this is a volatile field.
`Type`	`type()`	Returns the type of this field.
`String`	`typeName()`	Returns a text representation of the type of this field.

Methods declared in interface Accessible

isPackagePrivate, isPrivate, isProtected, isPublic, modifiers

Modifier and Type	Method	Description
`boolean`	`isPackagePrivate()`	Determines if this object mirrors a package private item.
`boolean`	`isPrivate()`	Determines if this object mirrors a private item.
`boolean`	`isProtected()`	Determines if this object mirrors a protected item.
`boolean`	`isPublic()`	Determines if this object mirrors a public item.
`int`	`modifiers()`	Returns the Java programming language modifiers, encoded in an integer.

Methods declared in interface Comparable

compareTo

Modifier and Type	Method	Description
`int`	`compareTo(Field o)`	Compares this object with the specified object for order.

Methods declared in interface Mirror

toString, virtualMachine

Modifier and Type	Method	Description
`String`	`toString()`	Returns a String describing this mirror
`VirtualMachine`	`virtualMachine()`	Gets the VirtualMachine to which this Mirror belongs.

Methods declared in interface TypeComponent

declaringType, genericSignature, isFinal, isStatic, isSynthetic, name, signature

Modifier and Type	Method	Description
`ReferenceType`	`declaringType()`	Returns the type in which this component was declared.
`String`	`genericSignature()`	Gets the generic signature for this TypeComponent if there is one.
`boolean`	`isFinal()`	Determines if this TypeComponent is final.
`boolean`	`isStatic()`	Determines if this TypeComponent is static.
`boolean`	`isSynthetic()`	Determines if this TypeComponent is synthetic.
`String`	`name()`	Gets the name of this type component.
`String`	`signature()`	Gets the type signature for this type component.

Method Details

typeName

String typeName()

Returns a text representation of the type of this field. Where the type is the type specified in the declaration of this field.

This type name is always available even if the type has not yet been created or loaded.

Returns:: a String representing the type of this field.

type

Type type() throws ClassNotLoadedException

Returns the type of this field. Where the type is the type specified in the declaration of this field.

For example, if a target class defines:

   short s;
   Date d;
   byte[] ba;

And the JDI client defines these Field objects:

   Field sField = targetClass.fieldByName("s");
   Field dField = targetClass.fieldByName("d");
   Field baField = targetClass.fieldByName("ba");

to mirror the corresponding fields, then sField.type() is a ShortType, dField.type() is the ReferenceType for java.util.Date and ((ArrayType)(baField.type())).componentType() is a ByteType.

Note: if the type of this field is a reference type (class, interface, or array) and it has not been created or loaded by the declaring type's class loader - that is, declaringType() .classLoader(), then ClassNotLoadedException will be thrown. Also, a reference type may have been loaded but not yet prepared, in which case the type will be returned but attempts to perform some operations on the returned type (e.g. fields()) will throw a ClassNotPreparedException. Use ReferenceType.isPrepared() to determine if a reference type is prepared.

Returns:

the Type of this field.

Throws:

ClassNotLoadedException - if the type has not yet been loaded or created through the appropriate class loader.

See Also:

isTransient

boolean isTransient()

Determine if this is a transient field.

Returns:: true if this field is transient; false otherwise.

isVolatile

boolean isVolatile()

Determine if this is a volatile field.

Returns:: true if this field is volatile; false otherwise.

isEnumConstant

boolean isEnumConstant()

Determine if this is a field that represents an enum constant.

Returns:: true if this field represents an enum constant; false otherwise.

equals

boolean equals(Object obj)

Compares the specified Object with this field for equality.

Overrides:

equals in class Object

Parameters:

obj - the reference object with which to compare.

Returns:

true if the Object is a Field and if both mirror the same field (declared in the same class or interface, in the same VM).

See Also:

hashCode

int hashCode()

Returns the hash code value for this Field.

Overrides:

hashCode in class Object

Returns:

the integer hash code.

See Also:

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