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/*
* esodata - data structures and other things, of varying utility
* Copyright 2022, Ben Culkin
*
* This program 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 3 of the License, or
* (at your option) any later version.
*
* This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
*/
package bjc.funcdata;
/**
* Indicates that an object can switch between immutable and mutable modes.
*
* Note that this only implements 'shallow' immutability. Namely, any sub-objects
* are not made immutable, and if the type is a collection, the elements are still
* as mutable as they were before.
*
* Implementations of this interface may choose to throw {@link ObjectFrozen} if
* you attempt to modify a frozen object, but they may also choose not to.
*
* @author Ben Culkin
* @param <F> The type of the implementing object
*/
public interface Freezable<F extends Freezable<?>> {
/**
* Freezes the internal state of this object, making it immutable.
*
* @return True if the object is frozen, false if it couldn't be frozen.
*/
public boolean freeze();
/**
* Thaws the internal state of this object, making it mutable.
*
* @return True if the object is thawed, false if it couldn't be thawed.
*/
public boolean thaw();
/**
* 'Deep-freeze' this object, making it immutable and disabling the ability to
* thaw it.
*
* @return True if the object was deep-frozen, false if that couldn't happen.
*/
default boolean deepFreeze() {
return false;
}
/**
* Check if this object can be frozen.
*
* @return Whether or not the object can be frozen.
*/
default boolean canFreeze() {
return false;
}
/**
* Checks if this object can be thawed.
*
* @return Whether or not the object can be thawed.
*/
default boolean canThaw() {
return false;
}
/**
* Determines if this object is frozen.
*
* @return True if the object is frozen, false if the object is thawed.
*/
public boolean isFrozen();
/**
* Determines if this object is thawed.
*
* @return True if the object is thawed, false if the object is thawed.
*/
default boolean isThawed() {
return !isFrozen();
}
/**
* Clone this object in a thawed state.
*
* @return A thawed clone of this object
*
* @throws CloneNotSupportedException If the underlying object doesn't support cloning
*/
default F cloneAsThawed() throws CloneNotSupportedException {
throw new CloneNotSupportedException();
}
}
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