jdk/src/share/classes/java/lang/Class.java
/**
* Returns a {@code Method} object that reflects the specified public
* member method of the class or interface represented by this
* {@code Class} object. The {@code name} parameter is a
* {@code String} specifying the simple name of the desired method. The
* {@code parameterTypes} parameter is an array of {@code Class}
* objects that identify the method's formal parameter types, in declared
* order. If {@code parameterTypes} is {@code null}, it is
* treated as if it were an empty array.
*
* <p> If the {@code name} is "{@code <init>};"or "{@code <clinit>}" a
* {@code NoSuchMethodException} is raised. Otherwise, the method to
* be reflected is determined by the algorithm that follows. Let C be the
* class represented by this object:
* <OL>
* <LI> C is searched for any <I>matching methods</I>. If no matching
* method is found, the algorithm of step 1 is invoked recursively on
* the superclass of C.</LI>
* <LI> If no method was found in step 1 above, the superinterfaces of C
* are searched for a matching method. If any such method is found, it
* is reflected.</LI>
* </OL>
*
* To find a matching method in a class C: If C declares exactly one
* public method with the specified name and exactly the same formal
* parameter types, that is the method reflected. If more than one such
* method is found in C, and one of these methods has a return type that is
* more specific than any of the others, that method is reflected;
* otherwise one of the methods is chosen arbitrarily.
*
* <p>Note that there may be more than one matching method in a
* class because while the Java language forbids a class to
* declare multiple methods with the same signature but different
* return types, the Java virtual machine does not. This
* increased flexibility in the virtual machine can be used to
* implement various language features. For example, covariant
* returns can be implemented with {@linkplain
* java.lang.reflect.Method#isBridge bridge methods}; the bridge
* method and the method being overridden would have the same
* signature but different return types.
*
* <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.4.
*
* @param name the name of the method
* @param parameterTypes the list of parameters
* @return the {@code Method} object that matches the specified
* {@code name} and {@code parameterTypes}
* @exception NoSuchMethodException if a matching method is not found
* or if the name is "<init>"or "<clinit>".
* @exception NullPointerException if {@code name} is {@code null}
* @exception SecurityException
* If a security manager, <i>s</i>, is present and any of the
* following conditions is met:
*
* <ul>
*
* <li> invocation of
* {@link SecurityManager#checkMemberAccess
* s.checkMemberAccess(this, Member.PUBLIC)} denies
* access to the method
*
* <li> the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
* </ul>
*
* @since JDK1.1
*/
public Method getMethod(String name, Class<?>... parameterTypes)
throws NoSuchMethodException, SecurityException {
{- -------------------------------------------
(1) 対象クラスの public メソッドにアクセス可能かどうかをチェックしておく.
(アクセスできない場合は SecurityException が出るためここで終了)
---------------------------------------- -}
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
{- -------------------------------------------
(1) getMethod0() メソッドを呼んで, name 引数と parameterTypes 引数で指定されたメソッドを取得し, リターンする.
(もし見つからなければ NoSuchMethodException)
---------------------------------------- -}
Method method = getMethod0(name, parameterTypes);
if (method == null) {
throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
}
return method;
}
This document is available under the GNU GENERAL PUBLIC LICENSE Version 2.