https://openjdk.java.net/ 
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package com.sun.jdi;

import java.util.List;


A static or instance method in the target VM. See TypeComponent for general information about Field and Method mirrors. 
Author:Robert Field, Gordon Hirsch, James McIlree
See Also:
Since: 1.3
/**
 * A static or instance method in the target VM. See {@link TypeComponent}
 * for general information about Field and Method mirrors.
 *
 * @see ObjectReference
 * @see ReferenceType
 *
 * @author Robert Field
 * @author Gordon Hirsch
 * @author James McIlree
 * @since  1.3
 */
@jdk.Exported
public interface Method extends TypeComponent, Locatable, Comparable<Method> {

    
Returns a text representation of the return type,
as specified in the declaration of this method.


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

Returns:a String containing the return type name.
/**
     * Returns a text representation of the return type,
     * as specified in the declaration of this method.
     * <P>
     * This type name is always available even if
     * the type has not yet been created or loaded.
     *
     * @return a String containing the return type name.
     */
    String returnTypeName();

    
Returns the return type,
as specified in the declaration of this method.

 Note: if the return type of this method 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. 
Throws:
See Also:
Returns:the return Type of this method.
/**
     * Returns the return type,
     * as specified in the declaration of this method.
     * <P>
     * Note: if the return type of this method 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,
     * {@link TypeComponent#declaringType <CODE>declaringType()</CODE>}
     * <CODE>.classLoader()</CODE>,
     * 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. {@link ReferenceType#fields() fields()}) will throw
     * a {@link ClassNotPreparedException}.
     * Use {@link ReferenceType#isPrepared()} to determine if
     * a reference type is prepared.
     *
     * @see Type
     * @see Field#type() Field.type() - for usage examples
     * @return the return {@link Type} of this method.
     * @throws ClassNotLoadedException if the type has not yet been
     * created or loaded
     * through the appropriate class loader.
     */
    Type returnType() throws ClassNotLoadedException;

    
Returns a list containing a text representation of the type
of each formal parameter of this method.


This list is always available even if
the types have not yet been created or loaded.

Returns:a List of String, one List element for each parameter of this method. Each element represents the type of a formal parameter as specified at compile-time. If the formal parameter was declared with an ellipsis, then it is represented as an array of the type before the ellipsis.
/**
     * Returns a list containing a text representation of the type
     * of each formal parameter of this method.
     * <P>
     * This list is always available even if
     * the types have not yet been created or loaded.
     *
     * @return a {@link java.util.List List} of {@link String},
     * one List element for each parameter of this method.
     * Each element represents the type of a formal parameter
     * as specified at compile-time.
     * If the formal parameter was declared with an ellipsis, then
     * it is represented as an array of the type before the ellipsis.
     *
     */
    List<String> argumentTypeNames();

    
Returns a list containing the type
of each formal parameter of this method.

 Note: if there is any parameter whose type 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 list will be returned but attempts to perform some operations on the type (e.g. fields()) will throw a ClassNotPreparedException. Use ReferenceType.isPrepared() to determine if a reference type is prepared. 
Throws:
See Also:
Returns:return a List of Type, one List element for each parameter of this method. Each element represents the type of a formal parameter as specified at compile-time. If the formal parameter was declared with an ellipsis, then it is represented as an array of the type before the ellipsis.
/**
     * Returns a list containing the type
     * of each formal parameter of this method.
     * <P>
     * Note: if there is any parameter whose type
     * 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,
     * {@link TypeComponent#declaringType <CODE>declaringType()</CODE>}
     * <CODE>.classLoader()</CODE>,
     * then ClassNotLoadedException will be thrown.
     * Also, a reference type may have been loaded but not yet prepared,
     * in which case the list will be returned
     * but attempts to perform some operations on the type
     * (e.g. {@link ReferenceType#fields() fields()}) will throw
     * a {@link ClassNotPreparedException}.
     * Use {@link ReferenceType#isPrepared()} to determine if
     * a reference type is prepared.
     *
     * @see Type
     * @return return a {@link java.util.List List} of {@link Type},
     * one List element for each parameter of this method.
     * Each element represents the type of a formal parameter
     * as specified at compile-time.
     * If the formal parameter was declared with an ellipsis, then
     * it is represented as an array of the type before the ellipsis.
     *
     * @throws ClassNotLoadedException if the type has not yet been loaded
     * through the appropriate class loader.
     */
    List<Type> argumentTypes() throws ClassNotLoadedException;

    
Determine if this method is abstract.

Returns:true if the method is declared abstract;
false otherwise.
/**
     * Determine if this method is abstract.
     *
     * @return <code>true</code> if the method is declared abstract;
     * false otherwise.
     */
    boolean isAbstract();

    
Determine if this method is a default method

Returns:true if the method is declared default;
false otherwise
Since:1.8
/**
     * Determine if this method is a default method
     *
     * @return <code>true</code> if the method is declared default;
     * false otherwise
     *
     * @since 1.8
     */
    default boolean isDefault() {
        throw new UnsupportedOperationException();
    }

    
Determine if this method is synchronized.

Returns:true if the method is declared synchronized;
false otherwise.
/**
     * Determine if this method is synchronized.
     *
     * @return <code>true</code> if the method is declared synchronized;
     * false otherwise.
     */
    boolean isSynchronized();

    
Determine if this method is native.

Returns:true if the method is declared native;
false otherwise.
/**
     * Determine if this method is native.
     *
     * @return <code>true</code> if the method is declared native;
     * false otherwise.
     */
    boolean isNative();

    
Determine if this method accepts a variable number of arguments.

Returns:true if the method accepts a variable number
of arguments, false otherwise.
Since:1.5
/**
     * Determine if this method accepts a variable number of arguments.
     *
     * @return <code>true</code> if the method accepts a variable number
     * of arguments, false otherwise.
     *
     * @since 1.5
     */
    boolean isVarArgs();

    
Determine if this method is a bridge method. Bridge
methods are defined in
The Java™ Language Specification.

Returns:true if the method is a bridge method,
false otherwise.
Since:1.5
/**
     * Determine if this method is a bridge method. Bridge
     * methods are defined in
     * <cite>The Java&trade; Language Specification</cite>.
     *
     * @return <code>true</code> if the method is a bridge method,
     * false otherwise.
     *
     * @since 1.5
     */
    boolean isBridge();

    
Determine if this method is a constructor.

Returns:true if the method is a constructor;
false otherwise.
/**
     * Determine if this method is a constructor.
     *
     * @return <code>true</code> if the method is a constructor;
     * false otherwise.
     */
    boolean isConstructor();

    
Determine if this method is a static initializer.

Returns:true if the method is a static initializer;
false otherwise.
/**
     * Determine if this method is a static initializer.
     *
     * @return <code>true</code> if the method is a static initializer;
     * false otherwise.
     */
    boolean isStaticInitializer();

    
Determine if this method is obsolete.

Returns:true if this method has been made obsolete by a VirtualMachine.redefineClasses operation.
Since:1.4
/**
     * Determine if this method is obsolete.
     *
     * @return <code>true</code> if this method has been made obsolete by a
     * {@link VirtualMachine#redefineClasses} operation.
     *
     * @since 1.4
     */
    boolean isObsolete();

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

This method is equivalent to
allLineLocations(vm.getDefaultStratum(),null) - see allLineLocations(String, String) for more information. 
Throws:
Returns:a List of all source line Location objects.
/**
     * Returns a list containing a {@link Location} object for
     * each executable source line in this method.
     * <P>
     * This method is equivalent to
     * <code>allLineLocations(vm.getDefaultStratum(),null)</code> -
     * see {@link #allLineLocations(String,String)}
     * for more information.
     *
     * @return a List of all source line {@link Location} objects.
     *
     * @throws AbsentInformationException if there is no line
     * number information for this (non-native, non-abstract)
     * method.
     */
    List<Location> allLineLocations() throws AbsentInformationException;

    
Returns a list containing a Location object for each executable source line in this method. 
 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 is ordered by code index (from low to high). 

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.


If the method is native or abstract, an empty list is
returned.


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 ReferenceType.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 (non-native, non-abstract)
method.  Or if sourceName is non-null
and source name information is not present.
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 method.
     * <P>
     * 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 is ordered by code index
     * (from low to high).
     * <P>
     * 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.
     * <P>
     * If the method is native or abstract, an empty list is
     * returned.
     * <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 ReferenceType#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 (non-native, non-abstract)
     * method.  Or if <i>sourceName</i> is non-<code>null</code>
     * and source name information is not present.
     *
     * @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:
Returns:a List of Location objects that map to the given line number.
/**
     * 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 {@link Location} objects that map to
     * the given line number.
     *
     * @throws AbsentInformationException if there is no line
     * number information for this method.
     */
    List<Location> locationsOfLine(int lineNumber) throws AbsentInformationException;

    
Returns a List containing all Location objects that map to the given line number and source name. 
 Returns a list containing each Location that maps to the given line. The returned list will contain a location for each disjoint range of code indices that have been assigned to the given line by the compiler and/or VM. Each returned location corresponds to the beginning of this range. An empty list will be returned if there is no executable code at the specified line number; specifically, native and abstract methods will always return an empty list. 

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 default
               stratum
  • sourceName – the source name containing the
                  line number, or null to match all
                  source names
  • lineNumber – the line number
Throws:
  • AbsentInformationException – if there is no line
number information for this method.
Or if sourceName is non-null
and source name information is not present.
Returns:a List of Location objects that map to the given line number.
Since:1.4
/**
     * Returns a List containing all {@link Location} objects
     * that map to the given line number and source name.
     * <P>
     * Returns a list containing each {@link Location} that maps
     * to the given line. The returned list will contain a
     * location for each disjoint range of code indices that have
     * been assigned to the given line by the compiler and/or
     * VM. Each returned location corresponds to the beginning of
     * this range.  An empty list will be returned if there is no
     * executable code at the specified line number; specifically,
     * native and abstract methods will always return an empty
     * list.
     * <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 null to use the default
     *                stratum
     * @param sourceName the source name containing the
     *                   line number, or null to match all
     *                   source names
     * @param lineNumber the line number
     *
     * @return a List of {@link Location} objects that map to
     * the given line number.
     *
     * @throws AbsentInformationException if there is no line
     * number information for this method.
     * Or if <i>sourceName</i> is non-<code>null</code>
     * and source name information is not present.
     *
     * @since 1.4
     */
    List<Location> locationsOfLine(String stratum, String sourceName,
                                   int lineNumber)
        throws AbsentInformationException;

    
Returns a Location for the given code index. 
Returns:the Location corresponding to the given code index or null if the specified code index is not a valid code index for this method (native and abstract methods will always return null).
/**
     * Returns a {@link Location} for the given code index.
     *
     * @return the {@link Location} corresponding to the
     * given code index or null if the specified code index is not a
     * valid code index for this method (native and abstract methods
     * will always return null).
     */
    Location locationOfCodeIndex(long codeIndex);

    
Returns a list containing each LocalVariable declared in this method. The list includes any variable declared in any scope within the method. It may contain multiple variables of the same name declared within disjoint scopes. Arguments are considered local variables and will be present in the returned list. If local variable information is not available, values of actual arguments to method invocations can be obtained by using the method StackFrame.getArgumentValues() 
Throws:
  • AbsentInformationException – if there is no variable
information for this method.
Generally, local variable information is not available for
native or abstract methods (that is, their argument name
information is not available), thus they will throw this exception.
Returns:the list of LocalVariable objects which mirror local variables declared in this method in the target VM. If there are no local variables, a zero-length list is returned.
/**
     * Returns a list containing each {@link LocalVariable} declared
     * in this method. The list includes any variable declared in any
     * scope within the method. It may contain multiple variables of the
     * same name declared within disjoint scopes. Arguments are considered
     * local variables and will be present in the returned list.
     *
     * If local variable information is not available, values of
     * actual arguments to method invocations can be obtained
     * by using the method {@link StackFrame#getArgumentValues()}
     *
     * @return the list of {@link LocalVariable} objects which mirror
     * local variables declared in this method in the target VM.
     * If there are no local variables, a zero-length list is returned.
     * @throws AbsentInformationException if there is no variable
     * information for this method.
     * Generally, local variable information is not available for
     * native or abstract methods (that is, their argument name
     * information is not available), thus they will throw this exception.
     */
    List<LocalVariable> variables() throws AbsentInformationException;

    
Returns a list containing each LocalVariable of a given name in this method. Multiple variables can be returned if the same variable name is used in disjoint scopes within the method. 
Throws:
  • AbsentInformationException – if there is no variable
information for this method.
Generally, local variable information is not available for
native or abstract methods (that is, their argument name
information is not available), thus they will throw this exception.
Returns:the list of LocalVariable objects of the given name. If there are no matching local variables, a zero-length list is returned.
/**
     * Returns a list containing each {@link LocalVariable} of a
     * given name in this method.
     * Multiple variables can be returned
     * if the same variable name is used in disjoint
     * scopes within the method.
     *
     * @return the list of {@link LocalVariable} objects of the given
     * name.
     * If there are no matching local variables, a zero-length list
     * is returned.
     * @throws AbsentInformationException if there is no variable
     * information for this method.
     * Generally, local variable information is not available for
     * native or abstract methods (that is, their argument name
     * information is not available), thus they will throw this exception.
     */
    List<LocalVariable> variablesByName(String name)
        throws AbsentInformationException;

    
Returns a list containing each LocalVariable that is declared as an argument of this method. If local variable information is not available, values of actual arguments to method invocations can be obtained by using the method StackFrame.getArgumentValues() 
Throws:
  • AbsentInformationException – if there is no variable
information for this method.
Generally, local variable information is not available for
native or abstract methods (that is, their argument name
information is not available), thus they will throw this exception.
Returns:the list of LocalVariable arguments. If there are no arguments, a zero-length list is returned.
/**
     * Returns a list containing each {@link LocalVariable} that is
     * declared as an argument of this method.
     *
     * If local variable information is not available, values of
     * actual arguments to method invocations can be obtained
     * by using the method {@link StackFrame#getArgumentValues()}
     *
     * @return the list of {@link LocalVariable} arguments.
     * If there are no arguments, a zero-length list is returned.
     * @throws AbsentInformationException if there is no variable
     * information for this method.
     * Generally, local variable information is not available for
     * native or abstract methods (that is, their argument name
     * information is not available), thus they will throw this exception.
     */
    List<LocalVariable> arguments() throws AbsentInformationException;

    
Returns an array containing the bytecodes for this method.

 Not all target virtual machines support this operation. Use VirtualMachine.canGetBytecodes() to determine if the operation is supported. 
Throws:
Returns:the array of bytecodes; abstract and native methods
will return a zero-length array.
/**
     * Returns an array containing the bytecodes for this method.
     * <P>
     * Not all target virtual machines support this operation.
     * Use {@link VirtualMachine#canGetBytecodes()}
     * to determine if the operation is supported.
     *
     * @return the array of bytecodes; abstract and native methods
     * will return a zero-length array.
     * @throws java.lang.UnsupportedOperationException if
     * the target virtual machine does not support
     * the retrieval of bytecodes.
     */
    byte[] bytecodes();

    
Returns the Location of this method, if there is executable code associated with it. 
Returns:the Location of this mirror, or null if this is an abstract method; native methods will return a Location object whose codeIndex is -1.
/**
     * Returns the {@link Location} of this method, if there
     * is executable code associated with it.
     *
     * @return the {@link Location} of this mirror, or null if
     * this is an abstract method; native methods will return a
     * Location object whose codeIndex is -1.
     */
    Location location();

    
Compares the specified Object with this method for equality.

Returns:true if the Object is a method and if both
mirror the same method (declared in the same class or interface, in
the same VM).
/**
     * Compares the specified Object with this method for equality.
     *
     * @return true if the Object is a method and if both
     * mirror the same method (declared in the same class or interface, in
     * the same VM).
     */
    boolean equals(Object obj);

    
Returns the hash code value for this Method.

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