/*
 * Copyright 2008-present MongoDB, Inc.
 *
 * 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
 *
 *   http://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
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package com.mongodb;

import static com.mongodb.assertions.Assertions.notNull;
import static java.lang.String.format;

A read concern level allows clients to choose a level of isolation for their reads.
@mongodb.server.release3.2
@mongodb.driver.manualreference/read-concern/#read-concern-levels Read Concern Levels
Since:3.2
/** * A read concern level allows clients to choose a level of isolation for their reads. * * @mongodb.server.release 3.2 * @mongodb.driver.manual reference/read-concern/#read-concern-levels Read Concern Levels * @since 3.2 */
public enum ReadConcernLevel {
The local read concern level.
/** * The local read concern level. */
LOCAL("local"),
The majority read concern level.
/** * The majority read concern level. */
MAJORITY("majority"),
The linearizable read concern level.

This read concern level is only compatible with ReadPreference.primary().

Since:3.4
@mongodb.server.release3.4
/** * The linearizable read concern level. * * <p> * This read concern level is only compatible with {@link ReadPreference#primary()}. * </p> * * @since 3.4 * @mongodb.server.release 3.4 */
LINEARIZABLE("linearizable"),
The snapshot read concern level.
Since:3.8
@mongodb.server.release4.0
/** * The snapshot read concern level. * * @since 3.8 * @mongodb.server.release 4.0 */
SNAPSHOT("snapshot"),
The available read concern level.
Since:3.9
@mongodb.server.release3.6
/** * The available read concern level. * * @since 3.9 * @mongodb.server.release 3.6 */
AVAILABLE("available"); private final String value; ReadConcernLevel(final String readConcernLevel) { this.value = readConcernLevel; }
Returns:the String representation of the read concern level that the MongoDB server understands or null for the default
/** * @return the String representation of the read concern level that the MongoDB server understands or null for the default */
public String getValue() { return value; }
Returns the ReadConcern from the string read concern level.
Params:
  • readConcernLevel – the read concern level string.
Returns:the read concern
/** * Returns the ReadConcern from the string read concern level. * * @param readConcernLevel the read concern level string. * @return the read concern */
public static ReadConcernLevel fromString(final String readConcernLevel) { notNull("readConcernLevel", readConcernLevel); for (ReadConcernLevel level : ReadConcernLevel.values()) { if (readConcernLevel.equalsIgnoreCase(level.value)) { return level; } } throw new IllegalArgumentException(format("'%s' is not a valid readConcernLevel", readConcernLevel)); } }