http://www.eclipse.org/jdt: Java Development Tools Core (Eclipse Foundation) 
Copyright (c) 2000, 2014 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
    IBM Corporation - added J2SE 1.5 support

/*******************************************************************************
 * Copyright (c) 2000, 2014 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     IBM Corporation - added J2SE 1.5 support
 *******************************************************************************/
package org.eclipse.jdt.core;


Represents a method (or constructor) declared in a type.

@noimplementThis interface is not intended to be implemented by clients.
/**
 * Represents a method (or constructor) declared in a type.
 *
 * @noimplement This interface is not intended to be implemented by clients.
 */
public interface IMethod extends IMember, IAnnotatable {

Returns a member value pair representing the default value of this method if any, or null if this method's parent is
not an annotation type, or else if this method does not have a default value.

 Note that IMemberValuePair.getValue() might return null.
Please see this method for more details.



Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
Returns:a member pair value if any, or null if none
Since:3.4
/**
 * Returns a {@link IMemberValuePair member value pair} representing the default
 * value of this method if any, or <code>null</code> if this method's parent is
 * not an annotation type, or else if this method does not have a default value.
 * <p>
 * Note that {@link IMemberValuePair#getValue()} might return <code>null</code>.
 * Please see this method for more details.
 * </p>
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @return a member pair value if any, or <code>null</code> if none
 * @since 3.4
 */
IMemberValuePair getDefaultValue() throws JavaModelException;

Returns the simple name of this method.
For a constructor, this returns the simple name of the declaring type.
Note: This holds whether the constructor appears in a source or binary type
(even though class files internally define constructor names to be "<init>").
For the class initialization methods in binary types, this returns
the special name "<clinit>".
This is a handle-only method.

Returns:the simple name of this method
/**
 * Returns the simple name of this method.
 * For a constructor, this returns the simple name of the declaring type.
 * Note: This holds whether the constructor appears in a source or binary type
 * (even though class files internally define constructor names to be <code>"&lt;init&gt;"</code>).
 * For the class initialization methods in binary types, this returns
 * the special name <code>"&lt;clinit&gt;"</code>.
 * This is a handle-only method.
 * @return the simple name of this method
 */
@Override
String getElementName();

Returns the type signatures of the exceptions this method throws,
in the order declared in the source. Returns an empty array
if this method throws no exceptions.


For example, a source method declaring "throws IOException",
would return the array {"QIOException;"}.



 The type signatures may be either unresolved (for source types) or resolved (for binary types), and either basic (for basic types) or rich (for parameterized types). See Signature for details. 


Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
See Also:
Returns:the type signatures of the exceptions this method throws,
in the order declared in the source, an empty array if this method throws no exceptions
/**
 * Returns the type signatures of the exceptions this method throws,
 * in the order declared in the source. Returns an empty array
 * if this method throws no exceptions.
 * <p>
 * For example, a source method declaring <code>"throws IOException"</code>,
 * would return the array <code>{"QIOException;"}</code>.
 * </p>
 * <p>
 * The type signatures may be either unresolved (for source types)
 * or resolved (for binary types), and either basic (for basic types)
 * or rich (for parameterized types). See {@link Signature} for details.
 * </p>
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @return the type signatures of the exceptions this method throws,
 * in the order declared in the source, an empty array if this method throws no exceptions
 * @see Signature
 */
String[] getExceptionTypes() throws JavaModelException;


Returns the formal type parameter signatures for this method.
Returns an empty array if this method has no formal type parameters.

 The formal type parameter signatures may be either unresolved (for source types) or resolved (for binary types). See Signature for details. 


Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
See Also:
Returns:the formal type parameter signatures of this method,
in the order declared in the source, an empty array if none
Since:3.0
Deprecated:Use getTypeParameters() instead
/**
 * Returns the formal type parameter signatures for this method.
 * Returns an empty array if this method has no formal type parameters.
 * <p>
 * The formal type parameter signatures may be either unresolved (for source
 * types) or resolved (for binary types). See {@link Signature} for details.
 * </p>
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @return the formal type parameter signatures of this method,
 * in the order declared in the source, an empty array if none
 * @see Signature
 * @since 3.0
 * @deprecated Use {@link #getTypeParameters()} instead
 */
String[] getTypeParameterSignatures() throws JavaModelException;

Returns the formal type parameters for this method.
Returns an empty array if this method has no formal type parameters.

Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
Returns:the formal type parameters of this method,
in the order declared in the source, an empty array if none
Since:3.1
/**
 * Returns the formal type parameters for this method.
 * Returns an empty array if this method has no formal type parameters.
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @return the formal type parameters of this method,
 * in the order declared in the source, an empty array if none
 * @since 3.1
 */
ITypeParameter[] getTypeParameters() throws JavaModelException;

Returns the number of parameters of this method.
This is a handle-only method.

Returns:the number of parameters of this method
/**
 * Returns the number of parameters of this method.
 * This is a handle-only method.
 *
 * @return the number of parameters of this method
 */
int getNumberOfParameters();


Returns the parameters of this method.

An empty array is returned, if the method has no parameters.


For binary types, associated source is used to retrieve the name range, source range and the flags.


These local variables can be used to retrieve the parameter annotations.


Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
Returns:the parameters of this method
Since:3.7
/**
 * Returns the parameters of this method.
 * <p>An empty array is returned, if the method has no parameters.</p>
 * <p>For binary types, associated source is used to retrieve the {@link ILocalVariable#getNameRange() name range},
 * {@link ILocalVariable#getSourceRange() source range} and the {@link ILocalVariable#getFlags() flags}.</p>
 * <p>These local variables can be used to retrieve the {@link ILocalVariable#getAnnotations() parameter annotations}.</p>
 * 
 * @return the parameters of this method
 * @throws JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @since 3.7
 */
ILocalVariable[] getParameters() throws JavaModelException;


Returns the binding key for this method only if the given method is resolved. A binding key is a key that uniquely identifies this method. It allows access to: 
    

  • generic info for parameterized methods
    • 

  • the actual return type for references to Object.getClass()
    • 

  • the actual parameter types and return type for references to signature polymorphic methods from class MethodHandle
    • 



If the given method is not resolved, the returned key is simply the java element's key.



See Also:
Returns:the binding key for this method
Since:3.1
/**
 * Returns the binding key for this method only if the given method is {@link #isResolved() resolved}.
 * A binding key is a key that uniquely identifies this method. It allows access to:
 * <ul>
 * <li>generic info for parameterized methods</li>
 * <li>the actual return type for references to {@link Object#getClass() Object.getClass()}</li>
 * <li>the actual parameter types and return type for references to signature polymorphic methods from class MethodHandle</li>
 * </ul>
 *
 * <p>If the given method is not resolved, the returned key is simply the java element's key.
 * </p>
 * @return the binding key for this method
 * @see org.eclipse.jdt.core.dom.IBinding#getKey()
 * @see BindingKey
 * @see #isResolved()
 * @since 3.1
 */
String getKey();

Returns the names of parameters in this method.
For binary types, associated source or attached Javadoc are used to retrieve the names.
If none can be retrieved, then these names are invented as "arg"+i, where i starts at 0.
Returns an empty array if this method has no parameters.

For example, a method declared as public void foo(String text, int length)
would return the array {"text","length"}.



Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
Returns:the names of parameters in this method, an empty array if this method has no parameters
/**
 * Returns the names of parameters in this method.
 * For binary types, associated source or attached Javadoc are used to retrieve the names.
 * If none can be retrieved, then these names are invented as "arg"+i, where i starts at 0.
 * Returns an empty array if this method has no parameters.
 *
 * <p>For example, a method declared as <code>public void foo(String text, int length)</code>
 * would return the array <code>{"text","length"}</code>.
 * </p>
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @return the names of parameters in this method, an empty array if this method has no parameters
 */
String[] getParameterNames() throws JavaModelException;

Returns the type signatures for the parameters of this method.
Returns an empty array if this method has no parameters.
This is a handle-only method.


For example, a source method declared as public void foo(String text, int length)
would return the array {"QString;","I"}.



 The type signatures may be either unresolved (for source types) or resolved (for binary types), and either basic (for basic types) or rich (for parameterized types). See Signature for details. 


See Also:
Returns:the type signatures for the parameters of this method, an empty array if this method has no parameters
/**
 * Returns the type signatures for the parameters of this method.
 * Returns an empty array if this method has no parameters.
 * This is a handle-only method.
 * <p>
 * For example, a source method declared as <code>public void foo(String text, int length)</code>
 * would return the array <code>{"QString;","I"}</code>.
 * </p>
 * <p>
 * The type signatures may be either unresolved (for source types)
 * or resolved (for binary types), and either basic (for basic types)
 * or rich (for parameterized types). See {@link Signature} for details.
 * </p>
 *
 * @return the type signatures for the parameters of this method, an empty array if this method has no parameters
 * @see Signature
 */
String[] getParameterTypes();

Returns the names of parameters in this method.
For binary types, these names are invented as "arg"+i, where i starts at 0
(even if source is associated with the binary or if Javdoc is attached to the binary).
Returns an empty array if this method has no parameters.

For example, a method declared as public void foo(String text, int length)
would return the array {"text","length"}. For the same method in a
binary, this would return {"arg0", "arg1"}.



Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
Returns:the names of parameters in this method, an empty array if this method has no parameters
Since:3.2
/**
 * Returns the names of parameters in this method.
 * For binary types, these names are invented as "arg"+i, where i starts at 0
 * (even if source is associated with the binary or if Javdoc is attached to the binary).
 * Returns an empty array if this method has no parameters.
 *
 * <p>For example, a method declared as <code>public void foo(String text, int length)</code>
 * would return the array <code>{"text","length"}</code>. For the same method in a
 * binary, this would return <code>{"arg0", "arg1"}</code>.
 * </p>
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @return the names of parameters in this method, an empty array if this method has no parameters
 * @since 3.2
 */
String[] getRawParameterNames() throws JavaModelException;

Returns the type signature of the return value of this method.
For constructors, this returns the signature for void.


For example, a source method declared as public String getName()
would return "QString;".



 The type signature may be either unresolved (for source types) or resolved (for binary types), and either basic (for basic types) or rich (for parameterized types). See Signature for details. 


Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
See Also:
Returns:the type signature of the return value of this method, void  for constructors
/**
 * Returns the type signature of the return value of this method.
 * For constructors, this returns the signature for void.
 * <p>
 * For example, a source method declared as <code>public String getName()</code>
 * would return <code>"QString;"</code>.
 * </p>
 * <p>
 * The type signature may be either unresolved (for source types)
 * or resolved (for binary types), and either basic (for basic types)
 * or rich (for parameterized types). See {@link Signature} for details.
 * </p>
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @return the type signature of the return value of this method, void  for constructors
 * @see Signature
 */
String getReturnType() throws JavaModelException;

Returns the signature of this method. This includes the signatures for the
parameter types and return type, but does not include the method name,
exception types, or type parameters.


For example, a source method declared as public void foo(String text, int length)
would return "(QString;I)V".



 The type signatures embedded in the method signature may be either unresolved (for source types) or resolved (for binary types), and either basic (for basic types) or rich (for parameterized types). See Signature for details. 


Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
See Also:
Returns:the signature of this method
/**
 * Returns the signature of this method. This includes the signatures for the
 * parameter types and return type, but does not include the method name,
 * exception types, or type parameters.
 * <p>
 * For example, a source method declared as <code>public void foo(String text, int length)</code>
 * would return <code>"(QString;I)V"</code>.
 * </p>
 * <p>
 * The type signatures embedded in the method signature may be either unresolved
 * (for source types) or resolved (for binary types), and either basic (for
 * basic types) or rich (for parameterized types). See {@link Signature} for
 * details.
 * </p>
 *
 * @return the signature of this method
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @see Signature
 */
String getSignature() throws JavaModelException;

Returns the type parameter declared in this method with the given name.
This is a handle-only method. The type parameter may or may not exist.

Params:
  • name – the given simple name
Returns:the type parameter declared in this method with the given name
Since:3.1
/**
 * Returns the type parameter declared in this method with the given name.
 * This is a handle-only method. The type parameter may or may not exist.
 *
 * @param name the given simple name
 * @return the type parameter declared in this method with the given name
 * @since 3.1
 */
ITypeParameter getTypeParameter(String name);

Returns whether this method is a constructor.

Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
Returns:true if this method is a constructor, false otherwise
/**
 * Returns whether this method is a constructor.
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 *
 * @return true if this method is a constructor, false otherwise
 */
boolean isConstructor() throws JavaModelException;


Returns whether this method is a main method.
It is a main method if:

    

  • its name is equal to "main"
    • 

  • its return type is void
    • 

  • it is static and public
    • 

  • it defines one parameter whose type's simple name is String[]
    • 



Throws:
  • JavaModelException – if this element does not exist or if an
     exception occurs while accessing its corresponding resource.
Since:2.0
Returns:true if this method is a main method, false otherwise
/**
 * Returns whether this method is a main method.
 * It is a main method if:
 * <ul>
 * <li>its name is equal to <code>"main"</code></li>
 * <li>its return type is <code>void</code></li>
 * <li>it is <code>static</code> and <code>public</code></li>
 * <li>it defines one parameter whose type's simple name is <code>String[]</code></li>
 * </ul>
 *
 * @exception JavaModelException if this element does not exist or if an
 *      exception occurs while accessing its corresponding resource.
 * @since 2.0
 * @return true if this method is a main method, false otherwise
 */
boolean isMainMethod() throws JavaModelException;


Returns whether this method represents a lambda expression.

Since:3.10
Returns:true if this method represents a lambda expression, false otherwise.
/**
 * Returns whether this method represents a lambda expression.
 *
 * @since 3.10
 * @return true if this method represents a lambda expression, false otherwise.
 */
boolean isLambdaMethod();


Returns whether this method represents a resolved method.
If a method is resolved, its key contains resolved information.

Returns:whether this method represents a resolved method.
Since:3.1
/**
 * Returns whether this method represents a resolved method.
 * If a method is resolved, its key contains resolved information.
 *
 * @return whether this method represents a resolved method.
 * @since 3.1
 */
boolean isResolved();

Returns whether this method is similar to the given method.
Two methods are similar if:

    

  • their element names are equal
    • 

  • they have the same number of parameters
    • 

  • the simple names of their parameter types are equal
    • 


This is a handle-only method.

Params:
  • method – the given method
See Also:
Returns:true if this method is similar to the given method.
Since:2.0
/**
 * Returns whether this method is similar to the given method.
 * Two methods are similar if:
 * <ul>
 * <li>their element names are equal</li>
 * <li>they have the same number of parameters</li>
 * <li>the simple names of their parameter types are equal</li>
 * </ul>
 * This is a handle-only method.
 *
 * @param method the given method
 * @return true if this method is similar to the given method.
 * @see Signature#getSimpleName(char[])
 * @since 2.0
 */
boolean isSimilar(IMethod method);
}