io.horizondb.model.schema.DatabaseDefinition.java Source code

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Here is the source code for io.horizondb.model.schema.DatabaseDefinition.java

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/**
 * Copyright 2013 Benjamin Lerer
 * 
 * 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
 * limitations under the License.
 */
package io.horizondb.model.schema;

import io.horizondb.io.ByteReader;
import io.horizondb.io.ByteWriter;
import io.horizondb.io.encoding.VarInts;
import io.horizondb.io.serialization.Parser;
import io.horizondb.io.serialization.Serializable;

import java.io.IOException;

import javax.annotation.concurrent.Immutable;

import org.apache.commons.lang.builder.EqualsBuilder;
import org.apache.commons.lang.builder.HashCodeBuilder;
import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;

/**
 * A database definition.
 */
@Immutable
public class DatabaseDefinition implements Serializable {

    /**
     * The parser instance.
     */
    private static final Parser<DatabaseDefinition> PARSER = new Parser<DatabaseDefinition>() {

        /**
         * {@inheritDoc}
         */
        @Override
        public DatabaseDefinition parseFrom(ByteReader reader) throws IOException {

            String name = VarInts.readString(reader);
            long timestamp = VarInts.readLong(reader);

            return new DatabaseDefinition(name, timestamp);
        }
    };

    /**
     * The database name.
     */
    private final String name;

    /**
     * The timestamp at which the database was created.
     */
    private final long timestamp;

    /**
     * Creates a new meta data with the specified name.
     * 
     * @param name the database name.
     */
    public DatabaseDefinition(String name) {

        this(name, System.currentTimeMillis());
    }

    /**
     * Creates a new meta data with the specified name.
     * 
     * @param name the database name.
     * @param timestamp the timestamp at which the database was created.
     */
    public DatabaseDefinition(String name, long timestamp) {

        this.name = name;
        this.timestamp = timestamp;
    }

    /**
     * Creates a new <code>DatabaseDefinition</code> by reading the data from the specified reader.
     * 
     * @param reader the reader to read from.
     * @throws IOException if an I/O problem occurs
     */
    public static DatabaseDefinition parseFrom(ByteReader reader) throws IOException {

        return getParser().parseFrom(reader);
    }

    /**
     * Returns the parser that can be used to deserialize <code>DatabaseDefinition</code> instances.
     * 
     * @return the parser that can be used to deserialize <code>DatabaseDefinition</code> instances.
     */
    public static Parser<DatabaseDefinition> getParser() {
        return PARSER;
    }

    /**
     * Returns the database name.
     * 
     * @return the database name.
     */
    public String getName() {
        return this.name;
    }

    /**
     * Returns the creation time.
     * @return the creation time.
     */
    public long getTimestamp() {
        return this.timestamp;
    }

    /**
     * Returns a new time series builder.
     * 
     * @param seriesName the name of the new time series
     * @return a new time series builder.
     */
    public TimeSeriesDefinition.Builder newTimeSeriesDefinitionBuilder(String seriesName) {

        return TimeSeriesDefinition.newBuilder(seriesName);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public int computeSerializedSize() {
        return VarInts.computeStringSize(this.name) + VarInts.computeLongSize(this.timestamp);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void writeTo(ByteWriter writer) throws IOException {
        VarInts.writeString(writer, this.name);
        VarInts.writeLong(writer, this.timestamp);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean equals(Object object) {
        if (object == this) {
            return true;
        }
        if (!(object instanceof DatabaseDefinition)) {
            return false;
        }
        DatabaseDefinition rhs = (DatabaseDefinition) object;
        return new EqualsBuilder().append(this.name, rhs.name).isEquals();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public int hashCode() {
        return new HashCodeBuilder(235543691, -72117241).append(this.name).toHashCode();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String toString() {
        return new ToStringBuilder(this, ToStringStyle.SHORT_PREFIX_STYLE).append("name", this.name)
                .append("timestamp", this.timestamp).toString();
    }

}