org.jboss.marshalling.FieldSetter Maven / Gradle / Ivy
/*
* JBoss, Home of Professional Open Source
* Copyright 2009, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.marshalling;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.security.AccessController;
import java.security.PrivilegedAction;
/**
* A setter for a (possibly final) field, which allows for correct object initialization of {@link java.io.Serializable} objects
* with {@code readObject()} methods, even in the presence of {@code final} fields.
*/
public final class FieldSetter {
private final Field field;
private FieldSetter(final Field field) {
this.field = field;
}
/**
* Set the value of the field to the given object.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void set(Object instance, Object value) throws IllegalArgumentException {
try {
field.set(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
/**
* Set the value of the field to the given value.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void setBoolean(Object instance, boolean value) throws IllegalArgumentException {
try {
field.setBoolean(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
/**
* Set the value of the field to the given value.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void setByte(Object instance, byte value) throws IllegalArgumentException {
try {
field.setByte(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
/**
* Set the value of the field to the given value.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void setChar(Object instance, char value) throws IllegalArgumentException {
try {
field.setChar(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
/**
* Set the value of the field to the given value.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void setDouble(Object instance, double value) throws IllegalArgumentException {
try {
field.setDouble(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
/**
* Set the value of the field to the given value.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void setFloat(Object instance, float value) throws IllegalArgumentException {
try {
field.setFloat(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
/**
* Set the value of the field to the given value.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void setInt(Object instance, int value) throws IllegalArgumentException {
try {
field.setInt(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
/**
* Set the value of the field to the given value.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void setLong(Object instance, long value) throws IllegalArgumentException {
try {
field.setLong(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
/**
* Set the value of the field to the given value.
*
* @param instance the instance to set
* @param value the new value
* @throws IllegalArgumentException if the given instance is {@code null} or not of the correct class
*/
public void setShort(Object instance, short value) throws IllegalArgumentException {
try {
field.setShort(instance, value);
} catch (IllegalAccessException e) {
throw illegalState(e);
}
}
private IllegalStateException illegalState(final IllegalAccessException e) {
return new IllegalStateException("Unexpected illegal access of accessible field", e);
}
/**
* Get an instance for the current class.
*
* @param clazz the class containing the field
* @param name the name of the field
* @return the {@code Field} instance
* @throws SecurityException if the field does not belong to the caller's class, or the field is static
* @throws IllegalArgumentException if there is no field of the given name on the given class
*/
public static FieldSetter get(final Class clazz, final String name) throws SecurityException, IllegalArgumentException {
final Class[] stackTrace = Holder.STACK_TRACE_READER.getClassContext();
if (stackTrace[2] != clazz) {
throw new SecurityException("Cannot get accessible field from someone else's class");
}
return new FieldSetter(AccessController.doPrivileged(new GetFieldAction(clazz, name)));
}
private static final class Holder {
static final StackTraceReader STACK_TRACE_READER;
static {
STACK_TRACE_READER = AccessController.doPrivileged(new PrivilegedAction() {
public StackTraceReader run() {
return new StackTraceReader();
}
});
}
private Holder() {
}
static final class StackTraceReader extends SecurityManager {
protected Class[] getClassContext() {
return super.getClassContext();
}
}
}
private static class GetFieldAction implements PrivilegedAction {
private final Class clazz;
private final String name;
private GetFieldAction(final Class clazz, final String name) {
this.clazz = clazz;
this.name = name;
}
public Field run() {
try {
final Field field = clazz.getDeclaredField(name);
final int modifiers = field.getModifiers();
if (Modifier.isStatic(modifiers)) {
throw new SecurityException("Cannot get access to static field '" + name + "'");
}
field.setAccessible(true);
return field;
} catch (NoSuchFieldException e) {
throw new IllegalArgumentException("No such field '" + name + "'", e);
}
}
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy