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/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package java.lang.reflect;
import sun.reflect.CallerSensitive;
import sun.reflect.ConstructorAccessor;
import sun.reflect.Reflection;
import sun.reflect.annotation.TypeAnnotation;
import sun.reflect.annotation.TypeAnnotationParser;
import sun.reflect.generics.repository.ConstructorRepository;
import sun.reflect.generics.factory.CoreReflectionFactory;
import sun.reflect.generics.factory.GenericsFactory;
import sun.reflect.generics.scope.ConstructorScope;
import java.lang.annotation.Annotation;
import java.lang.annotation.AnnotationFormatError;
/**
* {@code Constructor} provides information about, and access to, a single
* constructor for a class.
*
* <p>{@code Constructor} permits widening conversions to occur when matching the
* actual parameters to newInstance() with the underlying
* constructor's formal parameters, but throws an
* {@code IllegalArgumentException} if a narrowing conversion would occur.
*
* @param <T> the class in which the constructor is declared
*
* @see Member
* @see java.lang.Class
* @see java.lang.Class#getConstructors()
* @see java.lang.Class#getConstructor(Class[])
* @see java.lang.Class#getDeclaredConstructors()
*
* @author Kenneth Russell
* @author Nakul Saraiya
*/
public final class Constructor<T> extends Executable {
private Class<T> clazz;
private int slot;
private Class<?>[] parameterTypes;
private Class<?>[] exceptionTypes;
private int modifiers;
// Generics and annotations support
private transient String signature;
// generic info repository; lazily initialized
private transient ConstructorRepository genericInfo;
private byte[] annotations;
private byte[] parameterAnnotations;
// Generics infrastructure
// Accessor for factory
private GenericsFactory getFactory() {
// create scope and factory
return CoreReflectionFactory.make(this, ConstructorScope.make(this));
}
// Accessor for generic info repository
@Override
ConstructorRepository getGenericInfo() {
// lazily initialize repository if necessary
if (genericInfo == null) {
// create and cache generic info repository
genericInfo =
ConstructorRepository.make(getSignature(),
getFactory());
}
return genericInfo; //return cached repository
}
private volatile ConstructorAccessor constructorAccessor;
// For sharing of ConstructorAccessors. This branching structure
// is currently only two levels deep (i.e., one root Constructor
// and potentially many Constructor objects pointing to it.)
//
// If this branching structure would ever contain cycles, deadlocks can
// occur in annotation code.
private Constructor<T> root;
/**
* Used by Excecutable for annotation sharing.
*/
@Override
Executable getRoot() {
return root;
}
/**
* Package-private constructor used by ReflectAccess to enable
* instantiation of these objects in Java code from the java.lang
* package via sun.reflect.LangReflectAccess.
*/
Constructor(Class<T> declaringClass,
Class<?>[] parameterTypes,
Class<?>[] checkedExceptions,
int modifiers,
int slot,
String signature,
byte[] annotations,
byte[] parameterAnnotations) {
this.clazz = declaringClass;
this.parameterTypes = parameterTypes;
this.exceptionTypes = checkedExceptions;
this.modifiers = modifiers;
this.slot = slot;
this.signature = signature;
this.annotations = annotations;
this.parameterAnnotations = parameterAnnotations;
}
/**
* Package-private routine (exposed to java.lang.Class via
* ReflectAccess) which returns a copy of this Constructor. The copy's
* "root" field points to this Constructor.
*/
Constructor<T> copy() {
// This routine enables sharing of ConstructorAccessor objects
// among Constructor objects which refer to the same underlying
// method in the VM. (All of this contortion is only necessary
// because of the "accessibility" bit in AccessibleObject,
// which implicitly requires that new java.lang.reflect
// objects be fabricated for each reflective call on Class
// objects.)
if (this.root != null)
throw new IllegalArgumentException("Can not copy a non-root Constructor");
Constructor<T> res = new Constructor<>(clazz,
parameterTypes,
exceptionTypes, modifiers, slot,
signature,
annotations,
parameterAnnotations);
res.root = this;
// Might as well eagerly propagate this if already present
res.constructorAccessor = constructorAccessor;
return res;
}
@Override
boolean hasGenericInformation() {
return (getSignature() != null);
}
@Override
byte[] getAnnotationBytes() {
return annotations;
}
/**
* {@inheritDoc}
*/
@Override
public Class<T> getDeclaringClass() {
return clazz;
}
/**
* Returns the name of this constructor, as a string. This is
* the binary name of the constructor's declaring class.
*/
@Override
public String getName() {
return getDeclaringClass().getName();
}
/**
* {@inheritDoc}
*/
@Override
public int getModifiers() {
return modifiers;
}
/**
* {@inheritDoc}
* @throws GenericSignatureFormatError {@inheritDoc}
* @since 1.5
*/
@Override
@SuppressWarnings({"rawtypes", "unchecked"})
public TypeVariable<Constructor<T>>[] getTypeParameters() {
if (getSignature() != null) {
return (TypeVariable<Constructor<T>>[])getGenericInfo().getTypeParameters();
} else
return (TypeVariable<Constructor<T>>[])new TypeVariable[0];
}
/**
* {@inheritDoc}
*/
@Override
public Class<?>[] getParameterTypes() {
return parameterTypes.clone();
}
/**
* {@inheritDoc}
*/
public int getParameterCount() { return parameterTypes.length; }
/**
* {@inheritDoc}
* @throws GenericSignatureFormatError {@inheritDoc}
* @throws TypeNotPresentException {@inheritDoc}
* @throws MalformedParameterizedTypeException {@inheritDoc}
* @since 1.5
*/
@Override
public Type[] getGenericParameterTypes() {
return super.getGenericParameterTypes();
}
/**
* {@inheritDoc}
*/
@Override
public Class<?>[] getExceptionTypes() {
return exceptionTypes.clone();
}
/**
* {@inheritDoc}
* @throws GenericSignatureFormatError {@inheritDoc}
* @throws TypeNotPresentException {@inheritDoc}
* @throws MalformedParameterizedTypeException {@inheritDoc}
* @since 1.5
*/
@Override
public Type[] getGenericExceptionTypes() {
return super.getGenericExceptionTypes();
}
/**
* Compares this {@code Constructor} against the specified object.
* Returns true if the objects are the same. Two {@code Constructor} objects are
* the same if they were declared by the same class and have the
* same formal parameter types.
*/
public boolean equals(Object obj) {
if (obj != null && obj instanceof Constructor) {
Constructor<?> other = (Constructor<?>)obj;
if (getDeclaringClass() == other.getDeclaringClass()) {
return equalParamTypes(parameterTypes, other.parameterTypes);
}
}
return false;
}
/**
* Returns a hashcode for this {@code Constructor}. The hashcode is
* the same as the hashcode for the underlying constructor's
* declaring class name.
*/
public int hashCode() {
return getDeclaringClass().getName().hashCode();
}
/**
* Returns a string describing this {@code Constructor}. The string is
* formatted as the constructor access modifiers, if any,
* followed by the fully-qualified name of the declaring class,
* followed by a parenthesized, comma-separated list of the
* constructor's formal parameter types. For example:
* <pre>
* public java.util.Hashtable(int,float)
* </pre>
*
* <p>The only possible modifiers for constructors are the access
* modifiers {@code public}, {@code protected} or
* {@code private}. Only one of these may appear, or none if the
* constructor has default (package) access.
*
* @return a string describing this {@code Constructor}
* @jls 8.8.3. Constructor Modifiers
*/
public String toString() {
return sharedToString(Modifier.constructorModifiers(),
false,
parameterTypes,
exceptionTypes);
}
@Override
void specificToStringHeader(StringBuilder sb) {
sb.append(getDeclaringClass().getTypeName());
}
/**
* Returns a string describing this {@code Constructor},
* including type parameters. The string is formatted as the
* constructor access modifiers, if any, followed by an
* angle-bracketed comma separated list of the constructor's type
* parameters, if any, followed by the fully-qualified name of the
* declaring class, followed by a parenthesized, comma-separated
* list of the constructor's generic formal parameter types.
*
* If this constructor was declared to take a variable number of
* arguments, instead of denoting the last parameter as
* "<tt><i>Type</i>[]</tt>", it is denoted as
* "<tt><i>Type</i>...</tt>".
*
* A space is used to separate access modifiers from one another
* and from the type parameters or return type. If there are no
* type parameters, the type parameter list is elided; if the type
* parameter list is present, a space separates the list from the
* class name. If the constructor is declared to throw
* exceptions, the parameter list is followed by a space, followed
* by the word "{@code throws}" followed by a
* comma-separated list of the thrown exception types.
*
* <p>The only possible modifiers for constructors are the access
* modifiers {@code public}, {@code protected} or
* {@code private}. Only one of these may appear, or none if the
* constructor has default (package) access.
*
* @return a string describing this {@code Constructor},
* include type parameters
*
* @since 1.5
* @jls 8.8.3. Constructor Modifiers
*/
@Override
public String toGenericString() {
return sharedToGenericString(Modifier.constructorModifiers(), false);
}
@Override
void specificToGenericStringHeader(StringBuilder sb) {
specificToStringHeader(sb);
}
/**
* Uses the constructor represented by this {@code Constructor} object to
* create and initialize a new instance of the constructor's
* declaring class, with the specified initialization parameters.
* Individual parameters are automatically unwrapped to match
* primitive formal parameters, and both primitive and reference
* parameters are subject to method invocation conversions as necessary.
*
* <p>If the number of formal parameters required by the underlying constructor
* is 0, the supplied {@code initargs} array may be of length 0 or null.
*
* <p>If the constructor's declaring class is an inner class in a
* non-static context, the first argument to the constructor needs
* to be the enclosing instance; see section 15.9.3 of
* <cite>The Java™ Language Specification</cite>.
*
* <p>If the required access and argument checks succeed and the
* instantiation will proceed, the constructor's declaring class
* is initialized if it has not already been initialized.
*
* <p>If the constructor completes normally, returns the newly
* created and initialized instance.
*
* @param initargs array of objects to be passed as arguments to
* the constructor call; values of primitive types are wrapped in
* a wrapper object of the appropriate type (e.g. a {@code float}
* in a {@link java.lang.Float Float})
*
* @return a new object created by calling the constructor
* this object represents
*
* @exception IllegalAccessException if this {@code Constructor} object
* is enforcing Java language access control and the underlying
* constructor is inaccessible.
* @exception IllegalArgumentException if the number of actual
* and formal parameters differ; if an unwrapping
* conversion for primitive arguments fails; or if,
* after possible unwrapping, a parameter value
* cannot be converted to the corresponding formal
* parameter type by a method invocation conversion; if
* this constructor pertains to an enum type.
* @exception InstantiationException if the class that declares the
* underlying constructor represents an abstract class.
* @exception InvocationTargetException if the underlying constructor
* throws an exception.
* @exception ExceptionInInitializerError if the initialization provoked
* by this method fails.
*/
@CallerSensitive
public T newInstance(Object ... initargs)
throws InstantiationException, IllegalAccessException,
IllegalArgumentException, InvocationTargetException
{
if (!override) {
if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
Class<?> caller = Reflection.getCallerClass();
checkAccess(caller, clazz, null, modifiers);
}
}
if ((clazz.getModifiers() & Modifier.ENUM) != 0)
throw new IllegalArgumentException("Cannot reflectively create enum objects");
ConstructorAccessor ca = constructorAccessor; // read volatile
if (ca == null) {
ca = acquireConstructorAccessor();
}
@SuppressWarnings("unchecked")
T inst = (T) ca.newInstance(initargs);
return inst;
}
/**
* {@inheritDoc}
* @since 1.5
*/
@Override
public boolean isVarArgs() {
return super.isVarArgs();
}
/**
* {@inheritDoc}
* @jls 13.1 The Form of a Binary
* @since 1.5
*/
@Override
public boolean isSynthetic() {
return super.isSynthetic();
}
// NOTE that there is no synchronization used here. It is correct
// (though not efficient) to generate more than one
// ConstructorAccessor for a given Constructor. However, avoiding
// synchronization will probably make the implementation more
// scalable.
private ConstructorAccessor acquireConstructorAccessor() {
// First check to see if one has been created yet, and take it
// if so.
ConstructorAccessor tmp = null;
if (root != null) tmp = root.getConstructorAccessor();
if (tmp != null) {
constructorAccessor = tmp;
} else {
// Otherwise fabricate one and propagate it up to the root
tmp = reflectionFactory.newConstructorAccessor(this);
setConstructorAccessor(tmp);
}
return tmp;
}
// Returns ConstructorAccessor for this Constructor object, not
// looking up the chain to the root
ConstructorAccessor getConstructorAccessor() {
return constructorAccessor;
}
// Sets the ConstructorAccessor for this Constructor object and
// (recursively) its root
void setConstructorAccessor(ConstructorAccessor accessor) {
constructorAccessor = accessor;
// Propagate up
if (root != null) {
root.setConstructorAccessor(accessor);
}
}
int getSlot() {
return slot;
}
String getSignature() {
return signature;
}
byte[] getRawAnnotations() {
return annotations;
}
byte[] getRawParameterAnnotations() {
return parameterAnnotations;
}
/**
* {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @since 1.5
*/
public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
return super.getAnnotation(annotationClass);
}
/**
* {@inheritDoc}
* @since 1.5
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