org.springframework.boot.actuate.audit.InMemoryAuditEventRepository Maven / Gradle / Ivy
/*
* Copyright 2012-2018 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.boot.actuate.audit;
import java.time.Instant;
import java.util.LinkedList;
import java.util.List;
import org.springframework.util.Assert;
/**
* In-memory {@link AuditEventRepository} implementation.
*
* @author Dave Syer
* @author Phillip Webb
* @author Vedran Pavic
*/
public class InMemoryAuditEventRepository implements AuditEventRepository {
private static final int DEFAULT_CAPACITY = 1000;
private final Object monitor = new Object();
/**
* Circular buffer of the event with tail pointing to the last element.
*/
private AuditEvent[] events;
private volatile int tail = -1;
public InMemoryAuditEventRepository() {
this(DEFAULT_CAPACITY);
}
public InMemoryAuditEventRepository(int capacity) {
this.events = new AuditEvent[capacity];
}
/**
* Set the capacity of this event repository.
* @param capacity the capacity
*/
public void setCapacity(int capacity) {
synchronized (this.monitor) {
this.events = new AuditEvent[capacity];
}
}
@Override
public void add(AuditEvent event) {
Assert.notNull(event, "AuditEvent must not be null");
synchronized (this.monitor) {
this.tail = (this.tail + 1) % this.events.length;
this.events[this.tail] = event;
}
}
@Override
public List find(String principal, Instant after, String type) {
LinkedList events = new LinkedList<>();
synchronized (this.monitor) {
for (int i = 0; i < this.events.length; i++) {
AuditEvent event = resolveTailEvent(i);
if (event != null && isMatch(principal, after, type, event)) {
events.addFirst(event);
}
}
}
return events;
}
private boolean isMatch(String principal, Instant after, String type,
AuditEvent event) {
boolean match = true;
match = match && (principal == null || event.getPrincipal().equals(principal));
match = match && (after == null || event.getTimestamp().isAfter(after));
match = match && (type == null || event.getType().equals(type));
return match;
}
private AuditEvent resolveTailEvent(int offset) {
int index = ((this.tail + this.events.length - offset) % this.events.length);
return this.events[index];
}
}