https://openjdk.java.net/ 
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package com.sun.jdi;

import java.util.List;
import java.util.Map;


The type of an object in a target VM. ReferenceType encompasses
classes, interfaces, and array types as defined in
The Java™ Language Specification. All ReferenceType objects belong to one of the following subinterfaces: ClassType for classes, InterfaceType for interfaces, and ArrayType for arrays. Note that primitive classes (for example, the reflected type of Integer.TYPE) are represented as ClassType. The VM creates Class objects for all three, so from the VM perspective, each ReferenceType maps to a distinct Class object. 
 ReferenceTypes can be obtained by querying a particular ObjectReference for its type or by getting a list of all reference types from the VirtualMachine. 

ReferenceType provides access to static type information such as
methods and fields and provides access to dynamic type
information such as the corresponding Class object and the classloader.


Any method on ReferenceType which directly or
indirectly takes ReferenceType as an parameter may throw VMDisconnectedException if the target VM is disconnected and the VMDisconnectEvent has been or is available to be read from the EventQueue. 

Any method on ReferenceType which directly or
indirectly takes ReferenceType as an parameter may throw VMOutOfMemoryException if the target VM has run out of memory. 

Any method on ReferenceType or which directly or indirectly takes
ReferenceType as parameter may throw ObjectCollectedException if the mirrored type has been unloaded. 
Author:Robert Field, Gordon Hirsch, James McIlree
See Also:
Since: 1.3
/**
 * The type of an object in a target VM. ReferenceType encompasses
 * classes, interfaces, and array types as defined in
 * <cite>The Java&trade; Language Specification</cite>.
 * All ReferenceType objects belong to one of the following
 * subinterfaces:
 * {@link ClassType} for classes,
 * {@link InterfaceType} for interfaces, and
 * {@link ArrayType} for arrays.
 * Note that primitive classes (for example, the
 * {@link ClassObjectReference#reflectedType() reflected type} of
 * {@link java.lang.Integer#TYPE Integer.TYPE})
 * are represented as ClassType.
 * The VM creates Class objects for all three, so from the VM perspective,
 * each ReferenceType maps to a distinct Class object.
 * <p>
 * ReferenceTypes can
 * be obtained by querying a particular {@link ObjectReference} for its
 * type or by getting a list of all reference types from the
 * {@link VirtualMachine}.
 * <p>
 * ReferenceType provides access to static type information such as
 * methods and fields and provides access to dynamic type
 * information such as the corresponding Class object and the classloader.
 * <p>
 * Any method on <code>ReferenceType</code> which directly or
 * indirectly takes <code>ReferenceType</code> as an parameter may throw
 * {@link com.sun.jdi.VMDisconnectedException} if the target VM is
 * disconnected and the {@link com.sun.jdi.event.VMDisconnectEvent} has been or is
 * available to be read from the {@link com.sun.jdi.event.EventQueue}.
 * <p>
 * Any method on <code>ReferenceType</code> which directly or
 * indirectly takes <code>ReferenceType</code> as an parameter may throw
 * {@link com.sun.jdi.VMOutOfMemoryException} if the target VM has run out of memory.
 * <p>
 * Any method on <code>ReferenceType</code> or which directly or indirectly takes
 * <code>ReferenceType</code> as parameter may throw
 * {@link com.sun.jdi.ObjectCollectedException} if the mirrored type has been unloaded.
 *
 * @see ObjectReference
 * @see ObjectReference#referenceType
 * @see VirtualMachine
 * @see VirtualMachine#allClasses
 *
 * @author Robert Field
 * @author Gordon Hirsch
 * @author James McIlree
 * @since  1.3
 */
public interface ReferenceType
    extends Type, Comparable<ReferenceType>, Accessible
{

    
Gets the fully qualified name of this type. The returned name
is formatted as it might appear in a Java programming langauge
declaration for objects of this type.

 For primitive classes the returned name is the name of the corresponding primitive type; for example, "int" is returned as the name of the class represented by Integer.TYPE. 
Returns:a string containing the type name.
/**
     * Gets the fully qualified name of this type. The returned name
     * is formatted as it might appear in a Java programming langauge
     * declaration for objects of this type.
     * <p>
     * For primitive classes
     * the returned name is the name of the corresponding primitive
     * type; for example, "int" is returned as the name of the class
     * represented by {@link java.lang.Integer#TYPE Integer.TYPE}.
     * @return a string containing the type name.
     */
    String name();

    
Gets the generic signature for this type if there is one.
Generic signatures are described in the
The Java™ Virtual Machine Specification.

Returns:a string containing the generic signature, or null
if there is no generic signature.
Since:1.5
/**
     * Gets the generic signature for this type if there is one.
     * Generic signatures are described in the
     * <cite>The Java&trade; Virtual Machine Specification</cite>.
     *
     * @return a string containing the generic signature, or <code>null</code>
     * if there is no generic signature.
     *
     * @since 1.5
     */
    String genericSignature();

    
Gets the classloader object which loaded the class corresponding
to this type.

Returns:a ClassLoaderReference which mirrors the classloader, or null if the class was loaded through the bootstrap class
loader.
/**
     * Gets the classloader object which loaded the class corresponding
     * to this type.
     *
     * @return a {@link ClassLoaderReference} which mirrors the classloader,
     * or <code>null</code> if the class was loaded through the bootstrap class
     * loader.
     */
    ClassLoaderReference classLoader();

    
Gets an identifying name for the source corresponding to the
declaration of this type. Interpretation of this string is
the responsibility of the source repository mechanism.

 The returned name is dependent on VM's default stratum (VirtualMachine.getDefaultStratum()). In the reference implementation, when using the base stratum, the returned string is the unqualified name of the source file containing the declaration of this type. In other strata the returned source name is the first source name for that stratum. Since other languages may have more than one source name for a reference type, the use of Location.sourceName() or sourceNames(String) is preferred. 
 For arrays (ArrayType) and primitive classes, AbsentInformationException is always thrown. 
Throws:
Returns:the string source file name
/**
     * Gets an identifying name for the source corresponding to the
     * declaration of this type. Interpretation of this string is
     * the responsibility of the source repository mechanism.
     * <P>
     * The returned name is dependent on VM's default stratum
     * ({@link VirtualMachine#getDefaultStratum()}).
     * In the reference implementation, when using the base stratum,
     * the returned string is the
     * unqualified name of the source file containing the declaration
     * of this type.  In other strata the returned source name is
     * the first source name for that stratum.  Since other languages
     * may have more than one source name for a reference type,
     * the use of {@link Location#sourceName()} or
     * {@link #sourceNames(String)} is preferred.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * AbsentInformationException is always thrown.
     *
     * @return the string source file name
     * @throws AbsentInformationException if the source name is not
     * known
     */
    String sourceName() throws AbsentInformationException;

    
Gets the identifying names for all the source corresponding to the
declaration of this type. Interpretation of these names is
the responsibility of the source repository mechanism.

 The returned names are for the specified stratum (see Location for a description of strata). In the reference implementation, when using the Java programming language stratum, the returned List contains one element: a String which is the unqualified name of the source file containing the declaration of this type. In other strata the returned source names are all the source names defined for that stratum. 
Params:
  • stratum – The stratum to retrieve information from
or null for the declaring type's
default stratum.
Throws:
Returns:a List of String objects each representing a source name
Since:1.4
/**
     * Gets the identifying names for all the source corresponding to the
     * declaration of this type. Interpretation of these names is
     * the responsibility of the source repository mechanism.
     * <P>
     * The returned names are for the specified stratum
     * (see {@link Location} for a description of strata).
     * In the reference implementation, when using the Java
     * programming language stratum,
     * the returned List contains one element: a String which is the
     * unqualified name of the source file containing the declaration
     * of this type.  In other strata the returned source names are
     * all the source names defined for that stratum.
     *
     * @param stratum The stratum to retrieve information from
     * or <code>null</code> for the declaring type's
     * default stratum.
     *
     * @return a List of String objects each representing a source name
     *
     * @throws AbsentInformationException if the source names are not
     * known.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * AbsentInformationException is always thrown.
     *
     * @since 1.4
     */
    List<String> sourceNames(String stratum) throws AbsentInformationException;

    
Gets the paths to the source corresponding to the
declaration of this type. Interpretation of these paths is
the responsibility of the source repository mechanism.

 The returned paths are for the specified stratum (see Location for a description of strata). In the reference implementation, for strata which do not explicitly specify source path (the Java programming language stratum never does), the returned strings are the sourceNames(String) prefixed by the package name of this ReferenceType converted to a platform dependent path. For example, on a Windows platform, java.lang.Thread
would return a List containing one element:
"java\lang\Thread.java".

Params:
  • stratum – The stratum to retrieve information from
or null for the declaring type's
default stratum.
Throws:
Returns:a List of String objects each representing a source path
Since:1.4
/**
     * Gets the paths to the source corresponding to the
     * declaration of this type. Interpretation of these paths is
     * the responsibility of the source repository mechanism.
     * <P>
     * The returned paths are for the specified stratum
     * (see {@link Location} for a description of strata).
     * In the reference implementation, for strata which
     * do not explicitly specify source path (the Java
     * programming language stratum never does), the returned
     * strings are the {@link #sourceNames(String)} prefixed by
     * the package name of this ReferenceType
     * converted to a platform dependent path.
     * For example, on a Windows platform,
     * <CODE>java.lang.Thread</CODE>
     * would return a List containing one element:
     * <CODE>"java\lang\Thread.java"</CODE>.
     *
     * @param stratum The stratum to retrieve information from
     * or <code>null</code> for the declaring type's
     * default stratum.
     *
     * @return a List of String objects each representing a source path
     *
     * @throws AbsentInformationException if the source names are not
     * known.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * AbsentInformationException is always thrown.
     *
     * @since 1.4
     */
    List<String> sourcePaths(String stratum) throws AbsentInformationException;

    
Get the source debug extension of this type.

 Not all target virtual machines support this operation. Use canGetSourceDebugExtension() to determine if the operation is supported. 
Throws:
Returns:as a string the source debug extension attribute
/**
     * Get the source debug extension of this type.
     * <p>
     * Not all target virtual machines support this operation.
     * Use
     * {@link VirtualMachine#canGetSourceDebugExtension() canGetSourceDebugExtension()}
     * to determine if the operation is supported.
     * @return as a string the source debug extension attribute
     * @throws AbsentInformationException if the extension is not
     * specified
     * @throws java.lang.UnsupportedOperationException if
     * the target virtual machine does not support this
     * operation - see
     * {@link VirtualMachine#canGetSourceDebugExtension() canGetSourceDebugExtension()},
     */
    String sourceDebugExtension() throws AbsentInformationException;

    
Determines if this type was declared static. Only nested types,
can be declared static, so false is returned
for any package-level type, array type, or primitive class.

Returns:true if this type is static; false otherwise.
/**
     * Determines if this type was declared static. Only nested types,
     * can be declared static, so <code>false</code> is returned
     * for any package-level type, array type, or primitive class.
     *
     * @return <code>true</code> if this type is static; false otherwise.
     */
    boolean isStatic();

    
Determines if this type was declared abstract.

 For arrays (ArrayType) and primitive classes, the return value is undefined. 
Returns:true if this type is abstract; false otherwise.
/**
     * Determines if this type was declared abstract.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * the return value is undefined.
     *
     * @return <code>true</code> if this type is abstract; false otherwise.
     */
    boolean isAbstract();

    
Determines if this type was declared final.

 For arrays (ArrayType) and primitive classes, the return value is always true. 
Returns:true if this type is final; false otherwise.
/**
     * Determines if this type was declared final.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * the return value is always true.
     *
     * @return <code>true</code> if this type is final; false otherwise.
     */
    boolean isFinal();

    
Determines if this type has been prepared. See the JVM
specification for a definition of class preparation.

 For arrays (ArrayType) and primitive classes, the return value is undefined. 
Returns:true if this type is prepared; false otherwise.
/**
     * Determines if this type has been prepared. See the JVM
     * specification for a definition of class preparation.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * the return value is undefined.
     *
     * @return <code>true</code> if this type is prepared; false otherwise.
     */
    boolean isPrepared();

    
Determines if this type has been verified. See the JVM
specification for a definition of class verification.

 For arrays (ArrayType) and primitive classes, the return value is undefined. 
Returns:true if this type is verified; false otherwise.
/**
     * Determines if this type has been verified. See the JVM
     * specification for a definition of class verification.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * the return value is undefined.
     *
     * @return <code>true</code> if this type is verified; false otherwise.
     */
    boolean isVerified();

    
Determines if this type has been initialized. See the JVM specification for a definition of class verification. For InterfaceType, this method always returns the same value as isPrepared(). 
 For arrays (ArrayType) and primitive classes, the return value is undefined. 
Returns:true if this type is initialized; false otherwise.
/**
     * Determines if this type has been initialized. See the JVM
     * specification for a definition of class verification.
     * For {@link InterfaceType}, this method always returns the
     * same value as {@link #isPrepared()}.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * the return value is undefined.
     *
     * @return <code>true</code> if this type is initialized; false otherwise.
     */
    boolean isInitialized();

    
Determines if initialization failed for this class. See the JVM
specification for details on class initialization.

 For arrays (ArrayType) and primitive classes, the return value is undefined. 
Returns:true if initialization was attempted and
failed; false otherwise.
/**
     * Determines if initialization failed for this class. See the JVM
     * specification for details on class initialization.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes,
     * the return value is undefined.
     *
     * @return <code>true</code> if initialization was attempted and
     * failed; false otherwise.
     */
    boolean failedToInitialize();

    
Returns a list containing each Field declared in this type. Inherited fields are not included. Any synthetic fields created by the compiler are included in the list. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Throws:
Returns:a list Field objects; the list has length 0 if no fields exist.
/**
     * Returns a list containing each {@link Field} declared in this type.
     * Inherited fields are not included. Any synthetic fields created
     * by the compiler are included in the list.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @return a list {@link Field} objects; the list has length 0
     * if no fields exist.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    List<Field> fields();

    
Returns a list containing each unhidden and unambiguous Field in this type. Each field that can be accessed from the class or its instances with its simple name is included. Fields that are ambiguously multiply inherited or fields that are hidden by fields with the same name in a more recently inherited class cannot be accessed by their simple names and are not included in the returned list. All other inherited fields are included. See JLS section 8.3 for details. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Throws:
Returns:a List of Field objects; the list has length 0 if no visible fields exist.
/**
     * Returns a list containing each unhidden and unambiguous {@link Field}
     * in this type.
     * Each field that can be accessed from the class
     * or its instances with its simple name is included. Fields that
     * are ambiguously multiply inherited or fields that are hidden by
     * fields with the same name in a more recently inherited class
     * cannot be accessed
     * by their simple names and are not included in the returned
     * list. All other inherited fields are included.
     * See JLS section 8.3 for details.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @return a List of {@link Field} objects; the list has length
     * 0 if no visible fields exist.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    List<Field> visibleFields();

    
Returns a list containing each Field declared in this type, and its superclasses, implemented interfaces, and/or superinterfaces. All declared and inherited fields are included, regardless of whether they are hidden or multiply inherited. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Throws:
Returns:a List of Field objects; the list has length 0 if no fields exist.
/**
     * Returns a list containing each {@link Field} declared in this type,
     * and its superclasses, implemented interfaces, and/or superinterfaces.
     * All declared and inherited
     * fields are included, regardless of whether they are hidden or
     * multiply inherited.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @return a List of {@link Field} objects; the list has length
     * 0 if no fields exist.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    List<Field> allFields();

    
Finds the visible Field with the given non-ambiguous name. This method follows the inheritance rules specified in the JLS (8.3.3) to determine visibility. 
 For arrays (ArrayType) and primitive classes, the returned value is always null. 
Params:
  • fieldName – a String containing the name of desired field.
Throws:
Returns:a Field object which mirrors the found field, or null if there is no field with the given name or if the given name is ambiguous.
/**
     * Finds the visible {@link Field} with the given
     * non-ambiguous name. This method follows the
     * inheritance rules specified in the JLS (8.3.3) to determine
     * visibility.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * value is always null.
     *
     * @param fieldName a String containing the name of desired field.
     * @return a {@link Field} object which mirrors the found field, or
     * null if there is no field with the given name or if the given
     * name is ambiguous.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    Field fieldByName(String fieldName);

    
Returns a list containing each Method declared directly in this type. Inherited methods are not included. Constructors, the initialization method if any, and any synthetic methods created by the compiler are included in the list. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Throws:
Returns:a list Method objects; the list has length 0 if no methods exist.
/**
     * Returns a list containing each {@link Method} declared
     * directly in this type.
     * Inherited methods are not included. Constructors,
     * the initialization method if any, and any synthetic methods created
     * by the compiler are included in the list.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @return a list {@link Method} objects; the list has length 0
     * if no methods exist.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    List<Method> methods();

    
Returns a list containing each Method declared or inherited by this type. Methods from superclasses or superinterfaces that that have been hidden or overridden are not included. 
 Note that despite this exclusion, multiple inherited methods with the same signature can be present in the returned list, but at most one can be a member of a ClassType. See JLS section 8.4.6 for details. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Throws:
Returns:a List of Method objects; the list has length 0 if no visible methods exist.
/**
     * Returns a list containing each {@link Method}
     * declared or inherited by this type. Methods from superclasses
     * or superinterfaces that that have been hidden or overridden
     * are not included.
     * <p>
     * Note that despite this exclusion, multiple inherited methods
     * with the same signature can be present in the returned list, but
     * at most one can be a member of a {@link ClassType}.
     * See JLS section 8.4.6 for details.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @return a List of {@link Method} objects; the list has length
     * 0 if no visible methods exist.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    List<Method> visibleMethods();

    
Returns a list containing each Method declared in this type, and its superclasses, implemented interfaces, and/or superinterfaces. All declared and inherited methods are included, regardless of whether they are hidden or overridden. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Throws:
Returns:a List of Method objects; the list has length 0 if no methods exist.
/**
     * Returns a list containing each {@link Method} declared in this type,
     * and its superclasses, implemented interfaces, and/or superinterfaces.
     * All declared and inherited
     * methods are included, regardless of whether they are hidden or
     * overridden.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @return a List of {@link Method} objects; the list has length
     * 0 if no methods exist.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    List<Method> allMethods();

    
Returns a List containing each visible Method that has the given name. This is most commonly used to find overloaded methods. 

Overridden and hidden methods are not included.
See JLS (8.4.6) for details.

 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Params:
  • name – the name of the method to find.
Throws:
Returns:a List of Method objects that match the given name; the list has length 0 if no matching methods are found.
/**
     * Returns a List containing each visible {@link Method} that
     * has the given name.  This is most commonly used to
     * find overloaded methods.
     * <p>
     * Overridden and hidden methods are not included.
     * See JLS (8.4.6) for details.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @param name the name of the method to find.
     * @return a List of {@link Method} objects that match the given
     * name; the list has length 0 if no matching methods are found.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    List<Method> methodsByName(String name);

    
Returns a List containing each visible Method that has the given name and signature. The signature string is the JNI signature for the target method: 
    

  • ()V

  • ([Ljava/lang/String;)V

  • (IIII)Z


This method follows the inheritance rules specified
in the JLS (8.4.6) to determine visibility.

 At most one method in the list is a concrete method and a component of ClassType; any other methods in the list are abstract. Use ClassType.concreteMethodByName to retrieve only the matching concrete method. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Params:
  • name – the name of the method to find.
  • signature – the signature of the method to find
Throws:
Returns:a List of Method objects that match the given name and signature; the list has length 0 if no matching methods are found.
/**
     * Returns a List containing each visible {@link Method} that
     * has the given name and signature.
     * The signature string is the
     * JNI signature for the target method:
     * <ul>
     * <li><code>()V</code>
     * <li><code>([Ljava/lang/String;)V</code>
     * <li><code>(IIII)Z</code>
     * </ul>
     * This method follows the inheritance rules specified
     * in the JLS (8.4.6) to determine visibility.
     * <p>
     * At most one method in the list is a concrete method and a
     * component of {@link ClassType}; any other methods in the list
     * are abstract. Use {@link ClassType#concreteMethodByName} to
     * retrieve only the matching concrete method.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @param name the name of the method to find.
     * @param signature the signature of the method to find
     * @return a List of {@link Method} objects that match the given
     * name and signature; the list has length 0 if no matching methods
     * are found.
     * @throws ClassNotPreparedException if this class not yet been
     * prepared.
     */
    List<Method> methodsByName(String name, String signature);

    
Returns a List containing ReferenceType objects that are declared within this type and are currently loaded into the Virtual Machine. Both static nested types and non-static nested types (that is, inner types) are included. Local inner types (declared within a code block somewhere in this reference type) are also included in the returned list. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. 
Returns:a List of nested ReferenceType objects; the list has 0 length if there are no nested types.
/**
     * Returns a List containing {@link ReferenceType} objects that are
     * declared within this type and are currently loaded into the Virtual
     * Machine.  Both static nested types and non-static nested
     * types (that is, inner types) are included. Local inner types
     * (declared within a code block somewhere in this reference type) are
     * also included in the returned list.
     * <p>
     * For arrays ({@link ArrayType}) and primitive classes, the returned
     * list is always empty.
     *
     * @return a List of nested {@link ReferenceType} objects; the list
     * has 0 length if there are no nested types.
     */
    List<ReferenceType> nestedTypes();

    
Gets the Value of a given static Field in this type. The Field must be valid for this type; that is, it must be declared in this type, a superclass, a superinterface, or an implemented interface. 
Params:
  • field – the field containing the requested value
Throws:
Returns:the Value of the instance field.
/**
     * Gets the {@link Value} of a given static {@link Field} in this type.
     * The Field must be valid for this type;
     * that is, it must be declared in this type, a superclass, a
     * superinterface, or an implemented interface.
     *
     * @param field the field containing the requested value
     * @return the {@link Value} of the instance field.
     * @throws java.lang.IllegalArgumentException if the field is not valid for
     * this object's class.
     */
    Value getValue(Field field);

    
Returns a map containing the Value of each static Field in the given list. The Fields must be valid for this type; that is, they must be declared in this type, a superclass, a superinterface, or an implemented interface. 
Params:
  • fields – a list of Field objects containing the requested values.
Throws:
Returns:a Map of the requested Field objects with their Value.
/**
     * Returns a map containing the {@link Value} of each
     * static {@link Field} in the given list.
     * The Fields must be valid for this type;
     * that is, they must be declared in this type, a superclass, a
     * superinterface, or an implemented interface.
     *
     * @param fields a list of {@link Field} objects containing the
     * requested values.
     * @return a Map of the requested {@link Field} objects with
     * their {@link Value}.
     * @throws java.lang.IllegalArgumentException if any field is not valid for
     * this object's class.
     * @throws VMMismatchException if a {@link Mirror} argument and this mirror
     * do not belong to the same {@link VirtualMachine}.
     */
    Map<Field,Value> getValues(List<? extends Field> fields);

    
Returns the class object that corresponds to this type in the
target VM. The VM creates class objects for every kind of
ReferenceType: classes, interfaces, and array types.

Returns:the ClassObjectReference for this reference type in the target VM.
/**
     * Returns the class object that corresponds to this type in the
     * target VM. The VM creates class objects for every kind of
     * ReferenceType: classes, interfaces, and array types.
     * @return the {@link ClassObjectReference} for this reference type
     * in the target VM.
     */
    ClassObjectReference classObject();

    
Returns a list containing a Location object for each executable source line in this reference type. 

This method is equivalent to
allLineLocations(vm.getDefaultStratum(),null) - see allLineLocations(String, String) for more information. 
Throws:
/**
     * Returns a list containing a {@link Location} object
     * for each executable source line in this reference type.
     * <P>
     * This method is equivalent to
     * <code>allLineLocations(vm.getDefaultStratum(),null)</code> -
     * see {@link #allLineLocations(String,String)}
     * for more information.
     *
     * @throws AbsentInformationException if there is no line
     * number information for this class and there are non-native,
     * non-abstract executable members of this class.
     *
     * @throws ClassNotPreparedException if this class not yet
     * been prepared.
     */
    List<Location> allLineLocations() throws AbsentInformationException;

    
Returns a list containing a Location object for each executable source line in this reference type. Each location maps a source line to a range of code indices. The beginning of the range can be determined through Location.codeIndex. The returned list may contain multiple locations for a particular line number, if the compiler and/or VM has mapped that line to two or more disjoint code index ranges. Note that it is possible for the same source line to represent different code index ranges in different methods.

 For arrays (ArrayType) and primitive classes, the returned list is always empty. For interfaces (InterfaceType), the returned list will be non-empty only if the interface has executable code in its class initialization. 

Returned list is for the specified stratum (see Location for a description of strata). 
Params:
  • stratum – The stratum to retrieve information from
or null for the defaultStratum().
  • sourceName – Return locations only within this
source file or null to return locations.
Throws:
  • AbsentInformationException – if there is no line
number information for this class and there are non-native,
non-abstract executable members of this class.
Or if sourceName is non-null
and source name information is not present.
  • ClassNotPreparedException – if this class not yet
been prepared.
Returns:a List of all source line Location objects.
Since:1.4
/**
     * Returns a list containing a {@link Location} object
     * for each executable source line in this reference type.
     * Each location maps a source line to a range of code
     * indices.
     * The beginning of the range can be determined through
     * {@link Location#codeIndex}.  The returned list may contain
     * multiple locations for a particular line number, if the
     * compiler and/or VM has mapped that line to two or more
     * disjoint code index ranges.  Note that it is possible for
     * the same source line to represent different code index
     * ranges in <i>different</i> methods.
     * <P>
     * For arrays ({@link ArrayType}) and primitive classes, the
     * returned list is always empty.  For interfaces ({@link
     * InterfaceType}), the returned list will be non-empty only
     * if the interface has executable code in its class
     * initialization.
     * <P>
     * Returned list is for the specified <i>stratum</i>
     * (see {@link Location} for a description of strata).
     *
     * @param stratum The stratum to retrieve information from
     * or <code>null</code> for the {@link #defaultStratum()}.
     *
     * @param sourceName Return locations only within this
     * source file or <code>null</code> to return locations.
     *
     * @return a List of all source line {@link Location} objects.
     *
     * @throws AbsentInformationException if there is no line
     * number information for this class and there are non-native,
     * non-abstract executable members of this class.
     * Or if <i>sourceName</i> is non-<code>null</code>
     * and source name information is not present.
     *
     * @throws ClassNotPreparedException if this class not yet
     * been prepared.
     *
     * @since 1.4
     */
    List<Location> allLineLocations(String stratum, String sourceName)
                             throws AbsentInformationException;

    
Returns a List containing all Location objects that map to the given line number. 

This method is equivalent to
locationsOfLine(vm.getDefaultStratum(), null,
lineNumber) - see locationsOfLine(String, String, int) for more information. 
Params:
  • lineNumber – the line number
Throws:
See Also:
Returns:a List of all Location objects that map to the given line.
/**
     * Returns a List containing all {@link Location} objects
     * that map to the given line number.
     * <P>
     * This method is equivalent to
     * <code>locationsOfLine(vm.getDefaultStratum(), null,
     * lineNumber)</code> -
     * see {@link
     * #locationsOfLine(java.lang.String,java.lang.String,int)}
     * for more information.
     *
     * @param lineNumber the line number
     *
     * @return a List of all {@link Location} objects that map to
     * the given line.
     *
     * @throws AbsentInformationException if there is no line
     * number information for this class.
     *
     * @throws ClassNotPreparedException if this class not yet
     * been prepared.
     *
     * @see VirtualMachine#getDefaultStratum()
     */
    List<Location> locationsOfLine(int lineNumber)
        throws AbsentInformationException;

    
Returns a List containing all Location objects that map to the given line number. 
 For arrays (ArrayType) and primitive classes, the returned list is always empty. For interfaces (InterfaceType), the returned list will be non-empty only if the interface has executable code in its class initialization at the specified line number. An empty list will be returned if there is no executable code at the specified line number. 

Returned list is for the specified stratum (see Location for a description of strata). 
Params:
  • stratum – the stratum to use for comparing line number
               and source name, or null to use the defaultStratum().
  • sourceName – the source name containing the line
                  number, or null to match
                  all source names
  • lineNumber – the line number
Throws:
Returns:a List of all Location objects that map to the given line.
Since:1.4
/**
     * Returns a List containing all {@link Location} objects
     * that map to the given line number.
     * <P>
     * For arrays ({@link ArrayType}) and primitive classes, the
     * returned list is always empty.
     * For interfaces ({@link InterfaceType}), the returned list
     * will be non-empty only if the interface has executable code
     * in its class initialization at the specified line number.
     * An empty list will be returned if there is no executable
     * code at the specified line number.
     * <p>
     * Returned list is for the specified <i>stratum</i>
     * (see {@link Location} for a description of strata).
     *
     * @param stratum the stratum to use for comparing line number
     *                and source name, or <code>null</code> to
     *                use the {@link #defaultStratum()}.
     *
     * @param sourceName the source name containing the line
     *                   number, or <code>null</code> to match
     *                   all source names
     *
     * @param lineNumber the line number
     *
     * @return a List of all {@link Location} objects that map
     *         to the given line.
     *
     * @throws AbsentInformationException if there is no line
     *         number information for this class.
     *         Or if <i>sourceName</i> is non-<code>null</code>
     *         and source name information is not present.
     *
     * @throws ClassNotPreparedException if this class not yet
     *         been prepared.
     *
     * @since 1.4
     */
    List<Location> locationsOfLine(String stratum,
                                   String sourceName,
                                   int lineNumber)
                     throws AbsentInformationException;

    
Return the available strata for this reference type.

 See the Location for a description of strata. 
Returns:List of java.lang.String, each
representing a stratum
Since:1.4
/**
     * Return the available strata for this reference type.
     * <P>
     * See the {@link Location} for a description of strata.
     *
     * @return List of <CODE>java.lang.String</CODE>, each
     * representing a stratum
     *
     * @since 1.4
     */
    List<String> availableStrata();

    
Returns the default stratum for this reference type.
This value is specified in the class file and cannot
be set by the user.  If the class file does not
specify a default stratum the base stratum
("Java") will be returned.

 See the Location for a description of strata. 
Since:1.4
/**
     * Returns the default stratum for this reference type.
     * This value is specified in the class file and cannot
     * be set by the user.  If the class file does not
     * specify a default stratum the base stratum
     * (<code>"Java"</code>) will be returned.
     * <P>
     * See the {@link Location} for a description of strata.
     *
     * @since 1.4
     */
    String defaultStratum();

    
Returns instances of this ReferenceType.
Only instances that are reachable for the purposes of garbage collection
are returned.

 Not all target virtual machines support this operation. Use VirtualMachine.canGetInstanceInfo() to determine if the operation is supported. 
Params:
  • maxInstances – the maximum number of instances to return.
       Must be non-negative.  If zero, all instances are returned.
Throws:
See Also:
Returns:a List of ObjectReference objects. If there are no instances of this ReferenceType, a zero-length list is returned.
Since:1.6
/**
     * Returns instances of this ReferenceType.
     * Only instances that are reachable for the purposes of garbage collection
     * are returned.
     * <p>
     * Not all target virtual machines support this operation.
     * Use {@link VirtualMachine#canGetInstanceInfo()}
     * to determine if the operation is supported.
     *
     * @see VirtualMachine#instanceCounts(List)
     * @see ObjectReference#referringObjects(long)
     *
     * @param maxInstances the maximum number of instances to return.
     *        Must be non-negative.  If zero, all instances are returned.
     * @return a List of {@link ObjectReference} objects.  If there are
     * no instances of this ReferenceType, a zero-length list is returned.
     *
     * @throws java.lang.UnsupportedOperationException if
     * the target virtual machine does not support this
     * operation - see
     * {@link VirtualMachine#canGetInstanceInfo() canGetInstanceInfo()}
     * @throws java.lang.IllegalArgumentException if maxInstances is less
     *         than zero.
     * @since 1.6
     */
    List<ObjectReference> instances(long maxInstances);

    
Compares the specified Object with this ReferenceType for equality.

Returns: true if the Object is a ReferenceType, if the ReferenceTypes belong to the same VM, and if they mirror classes which correspond to the same instance of java.lang.Class in that VM.
/**
     * Compares the specified Object with this ReferenceType for equality.
     *
     * @return  true if the Object is a {@link ReferenceType}, if the
     * ReferenceTypes belong to the same VM, and if they mirror classes
     * which correspond to the same instance of java.lang.Class in that VM.
     */
    boolean equals(Object obj);

    
Returns the hash code value for this ObjectReference.

Returns:the integer hash code
/**
     * Returns the hash code value for this ObjectReference.
     *
     * @return the integer hash code
     */
    int hashCode();

    
Returns the class major version number, as defined in the class file format of the Java Virtual Machine Specification. For arrays (ArrayType) and primitive classes, the returned major version number value is zero. Not all target virtual machines support this operation. Use VirtualMachine.canGetClassFileVersion() to determine if the operation is supported. 
Throws:
Returns:the major version number of the class.
Since:1.6
/**
     * Returns the class major version number, as defined in the class file format
     * of the Java Virtual Machine Specification.
     *
     * For arrays ({@link ArrayType}) and primitive classes,
     * the returned major version number value is zero.
     *
     * Not all target virtual machines support this operation.
     * Use {@link VirtualMachine#canGetClassFileVersion()}
     * to determine if the operation is supported.
     *
     * @return the major version number of the class.
     *
     * @throws java.lang.UnsupportedOperationException if
     * the target virtual machine does not support this
     * operation - see
     * {@link VirtualMachine#canGetClassFileVersion() canGetClassFileVersion()}
     *
     * @since 1.6
     */
    int majorVersion();


    
Returns the class minor version number, as defined in the class file format of the Java Virtual Machine Specification. For arrays (ArrayType) and primitive classes, the returned minor version number value is zero. Not all target virtual machines support this operation. Use VirtualMachine.canGetClassFileVersion() to determine if the operation is supported. 
Throws:
Returns:the minor version number of the class.
Since:1.6
/**
     * Returns the class minor version number, as defined in the class file format
     * of the Java Virtual Machine Specification.
     *
     * For arrays ({@link ArrayType}) and primitive classes,
     * the returned minor version number value is zero.
     *
     * Not all target virtual machines support this operation.
     * Use {@link VirtualMachine#canGetClassFileVersion()}
     * to determine if the operation is supported.
     *
     * @return the minor version number of the class.
     *
     * @throws java.lang.UnsupportedOperationException if
     * the target virtual machine does not support this
     * operation - see
     * {@link VirtualMachine#canGetClassFileVersion() canGetClassFileVersion()}
     *
     * @since 1.6
     */
    int minorVersion();

    
Returns the number of entries in the constant pool plus one. This corresponds to the constant_pool_count item of the Class File Format in the Java Virtual Machine Specification. For arrays (ArrayType) and primitive classes, the returned constant pool count value is zero. Not all target virtual machines support this operation. Use VirtualMachine.canGetConstantPool() to determine if the operation is supported. 
Throws:
See Also:
Returns:total number of constant pool entries for a class plus one.
Since:1.6
/**
     * Returns the number of entries in the constant pool plus one.
     * This corresponds to the constant_pool_count item of the Class File Format
     * in the Java Virtual Machine Specification.
     *
     * For arrays ({@link ArrayType}) and primitive classes,
     * the returned constant pool count value is zero.
     *
     * Not all target virtual machines support this operation.
     * Use {@link VirtualMachine#canGetConstantPool()}
     * to determine if the operation is supported.
     *
     * @return total number of constant pool entries for a class plus one.
     *
     * @throws java.lang.UnsupportedOperationException if
     * the target virtual machine does not support this
     * operation - see
     * {@link VirtualMachine#canGetConstantPool() canGetConstantPool()}
     *
     * @see #constantPool()
     * @since 1.6
     */
    int constantPoolCount();

    
Returns the raw bytes of the constant pool in the format of the constant_pool item of the Class File Format in the Java Virtual Machine Specification. The format of the constant pool may differ between versions of the Class File Format, so, the minor and major class version numbers should be checked for compatibility. For arrays (ArrayType) and primitive classes, a zero length byte array is returned. Not all target virtual machines support this operation. Use VirtualMachine.canGetConstantPool() to determine if the operation is supported. 
Throws:
See Also:
Returns:the raw bytes of constant pool.
Since:1.6
/**
     * Returns the raw bytes of the constant pool in the format of the
     * constant_pool item of the Class File Format in the Java Virtual
     * Machine Specification. The format of the constant pool may
     * differ between versions of the Class File Format, so, the
     * minor and major class version numbers should be checked for
     * compatibility.
     *
     * For arrays ({@link ArrayType}) and primitive classes,
     * a zero length byte array is returned.
     *
     * Not all target virtual machines support this operation.
     * Use {@link VirtualMachine#canGetConstantPool()}
     * to determine if the operation is supported.
     *
     * @return the raw bytes of constant pool.
     *
     * @throws java.lang.UnsupportedOperationException if
     * the target virtual machine does not support this
     * operation - see
     * {@link VirtualMachine#canGetConstantPool() canGetConstantPool()}
     *
     * @see #constantPoolCount()
     * @since 1.6
     */
     byte[] constantPool();

}