io.permazen.schema.SchemaSupport Maven / Gradle / Ivy
/*
* Copyright (C) 2015 Archie L. Cobbs. All rights reserved.
*/
package io.permazen.schema;
import io.permazen.util.AbstractXMLStreaming;
/**
* Models one Permazen {@link io.permazen.core.Database} schema version.
*/
class SchemaSupport extends AbstractXMLStreaming implements Cloneable {
/*final*/ boolean lockedDown;
// Lockdown
/**
* Lock down this instance.
*
*
* Once locked down, any attempts to modify this instance (and all associated objects) will result
* in a {@link IllegalStateException}.
*/
public void lockDown() {
if (!this.lockedDown) {
this.lockDownRecurse();
this.lockedDown = true;
}
}
/**
* Determine whether this instance is {@linkplain #lockDown locked down}.
*
* @return true if instance is locked down, otherwise false
*/
public boolean isLockedDown() {
return this.lockedDown;
}
void lockDownRecurse() {
}
void verifyNotLockedDown() {
if (this.lockedDown)
throw new UnsupportedOperationException("instance is locked down");
}
// Cloneable
/**
* Deep-clone this instance.
*
*
* The returned instance will not be {@linkplain #lockDown locked down}.
*/
@Override
protected SchemaSupport clone() {
final SchemaSupport clone;
try {
clone = (SchemaSupport)super.clone();
} catch (CloneNotSupportedException e) {
throw new RuntimeException(e);
}
clone.lockedDown = false;
return clone;
}
}