| /* java.lang.reflect.Constructor - reflection of Java constructors |
| Copyright (C) 1998, 2001 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package java.lang.reflect; |
| |
| import java.util.Arrays; |
| |
| /** |
| * The Constructor class represents a constructor of a class. It also allows |
| * dynamic creation of an object, via reflection. Invocation on Constructor |
| * objects knows how to do widening conversions, but throws |
| * {@link IllegalArgumentException} if a narrowing conversion would be |
| * necessary. You can query for information on this Constructor regardless |
| * of location, but construction access may be limited by Java language |
| * access controls. If you can't do it in the compiler, you can't normally |
| * do it here either.<p> |
| * |
| * <B>Note:</B> This class returns and accepts types as Classes, even |
| * primitive types; there are Class types defined that represent each |
| * different primitive type. They are <code>java.lang.Boolean.TYPE, |
| * java.lang.Byte.TYPE,</code>, also available as <code>boolean.class, |
| * byte.class</code>, etc. These are not to be confused with the |
| * classes <code>java.lang.Boolean, java.lang.Byte</code>, etc., which are |
| * real classes.<p> |
| * |
| * Also note that this is not a serializable class. It is entirely feasible |
| * to make it serializable using the Externalizable interface, but this is |
| * on Sun, not me. |
| * |
| * @author John Keiser |
| * @author Eric Blake <ebb9@email.byu.edu> |
| * @see Member |
| * @see Class |
| * @see java.lang.Class#getConstructor(Object[]) |
| * @see java.lang.Class#getDeclaredConstructor(Object[]) |
| * @see java.lang.Class#getConstructors() |
| * @see java.lang.Class#getDeclaredConstructors() |
| * @since 1.1 |
| * @status updated to 1.4 |
| */ |
| public final class Constructor |
| extends AccessibleObject implements Member |
| { |
| private Class clazz; |
| private int slot; |
| |
| /** |
| * This class is uninstantiable except from native code. |
| */ |
| private Constructor(Class declaringClass,int slot) |
| { |
| this.clazz = declaringClass; |
| this.slot = slot; |
| } |
| |
| private Constructor() |
| { |
| } |
| |
| /** |
| * Gets the class that declared this constructor. |
| * @return the class that declared this member |
| */ |
| public Class getDeclaringClass() |
| { |
| return clazz; |
| } |
| |
| /** |
| * Gets the name of this constructor (the non-qualified name of the class |
| * it was declared in). |
| * @return the name of this constructor |
| */ |
| public String getName() |
| { |
| return getDeclaringClass().getName(); |
| } |
| |
| /** |
| * Gets the modifiers this constructor uses. Use the <code>Modifier</code> |
| * class to interpret the values. A constructor can only have a subset of the |
| * following modifiers: public, private, protected. |
| * |
| * @return an integer representing the modifiers to this Member |
| * @see Modifier |
| */ |
| public native int getModifiers(); |
| |
| /** |
| * Get the parameter list for this constructor, in declaration order. If the |
| * constructor takes no parameters, returns a 0-length array (not null). |
| * |
| * @return a list of the types of the constructor's parameters |
| */ |
| public native Class[] getParameterTypes(); |
| |
| /** |
| * Get the exception types this constructor says it throws, in no particular |
| * order. If the constructor has no throws clause, returns a 0-length array |
| * (not null). |
| * |
| * @return a list of the types in the constructor's throws clause |
| */ |
| public native Class[] getExceptionTypes(); |
| |
| /** |
| * Compare two objects to see if they are semantically equivalent. |
| * Two Constructors are semantically equivalent if they have the same |
| * declaring class and the same parameter list. This ignores different |
| * exception clauses, but since you can't create a Method except through the |
| * VM, this is just the == relation. |
| * |
| * @param o the object to compare to |
| * @return <code>true</code> if they are equal; <code>false</code> if not. |
| */ |
| public boolean equals(Object o) |
| { |
| if (!(o instanceof Constructor)) |
| return false; |
| Constructor that = (Constructor)o; |
| if (this.getDeclaringClass() != that.getDeclaringClass()) |
| return false; |
| if (!Arrays.equals(this.getParameterTypes(), that.getParameterTypes())) |
| return false; |
| return true; |
| } |
| |
| /** |
| * Get the hash code for the Constructor. The Constructor hash code is the |
| * hash code of the declaring class's name. |
| * |
| * @return the hash code for the object |
| */ |
| public int hashCode() |
| { |
| return getDeclaringClass().getName().hashCode(); |
| } |
| |
| /** |
| * Get a String representation of the Constructor. A Constructor's String |
| * representation is "<modifier> <classname>(<paramtypes>) |
| * throws <exceptions>", where everything after ')' is omitted if |
| * there are no exceptions.<br> Example: |
| * <code>public java.io.FileInputStream(java.lang.Runnable) |
| * throws java.io.FileNotFoundException</code> |
| * |
| * @return the String representation of the Constructor |
| */ |
| public String toString() |
| { |
| // 128 is a reasonable buffer initial size for constructor |
| StringBuffer sb = new StringBuffer(128); |
| Modifier.toString(getModifiers(), sb).append(' '); |
| sb.append(getDeclaringClass().getName()).append('('); |
| Class[] c = getParameterTypes(); |
| if (c.length > 0) |
| { |
| sb.append(c[0].getName()); |
| for (int i = 1; i < c.length; i++) |
| sb.append(',').append(c[i].getName()); |
| } |
| sb.append(')'); |
| c = getExceptionTypes(); |
| if (c.length > 0) |
| { |
| sb.append(" throws ").append(c[0].getName()); |
| for (int i = 1; i < c.length; i++) |
| sb.append(',').append(c[i].getName()); |
| } |
| return sb.toString(); |
| } |
| |
| /** |
| * Create a new instance by invoking the constructor. Arguments are |
| * automatically unwrapped and widened, if needed.<p> |
| * |
| * If this class is abstract, you will get an |
| * <code>InstantiationException</code>. If the constructor takes 0 |
| * arguments, you may use null or a 0-length array for <code>args</code>.<p> |
| * |
| * If this Constructor enforces access control, your runtime context is |
| * evaluated, and you may have an <code>IllegalAccessException</code> if |
| * you could not create this object in similar compiled code. If the class |
| * is uninitialized, you trigger class initialization, which may end in a |
| * <code>ExceptionInInitializerError</code>.<p> |
| * |
| * Then, the constructor is invoked. If it completes normally, the return |
| * value will be the new object. If it completes abruptly, the exception is |
| * wrapped in an <code>InvocationTargetException</code>. |
| * |
| * @param args the arguments to the constructor |
| * @return the newly created object |
| * @throws IllegalAccessException if the constructor could not normally be |
| * called by the Java code (i.e. it is not public) |
| * @throws IllegalArgumentException if the number of arguments is incorrect; |
| * or if the arguments types are wrong even with a widening |
| * conversion |
| * @throws InstantiationException if the class is abstract |
| * @throws InvocationTargetException if the constructor throws an exception |
| * @throws ExceptionInInitializerError if construction triggered class |
| * initialization, which then failed |
| */ |
| public Object newInstance(Object args[]) |
| throws InstantiationException, IllegalAccessException, |
| InvocationTargetException |
| { |
| return constructNative(args, clazz, slot); |
| } |
| |
| private native Object constructNative(Object[] args, Class declaringClass, |
| int slot) |
| throws InstantiationException, IllegalAccessException, |
| InvocationTargetException; |
| } |