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Permazen classes that map Java model classes onto the core API.
There is a newer version: 5.1.0

/*
 * Copyright (C) 2015 Archie L. Cobbs. All rights reserved.
 */

package io.permazen;

/**
 * {@link Session} modes.
 *
 * 
 * The three {@link SessionMode} values correspond to the three layers of abstraction in Permazen.
 * In order from bottom to top these are:
 * 

 *  The key/value database layer, providing {@link io.permazen.kv.KVDatabase}
 *      and {@link io.permazen.kv.KVTransaction} and represented by {@link #KEY_VALUE}
 *  The core API database layer, providing {@link io.permazen.core.Database}
 *      and {@link io.permazen.core.Transaction} and represented by {@link #CORE_API}
 *  The Permazen Java layer, providing {@link io.permazen.Permazen}
 *      and {@link io.permazen.JTransaction} and represented by {@link #PERMAZEN}
 * 
 */
public enum SessionMode {

    /**
     * Permazen key/value database mode.
     *
     * 
     * This is the lowest level CLI mode, where only the raw {@code byte[]} key/value store is available.
     * This mode provides a {@link io.permazen.kv.KVTransaction}, but no {@link io.permazen.core.Transaction}
     * or {@link io.permazen.JTransaction}.
     *
     * @see io.permazen.kv
     */
    KEY_VALUE(false, false),

    /**
     * Permazen Core API mode.
     *
     * 

     * Supports access to low level schema information, core API "objects" and fields, but no Java-specific operations.
     * This mode provides a {@link io.permazen.kv.KVTransaction} and {@link io.permazen.core.Transaction},
     * but no {@link io.permazen.JTransaction}.
     *
     * 

     * Schema information may be provided either by a schema XML file or by
     * {@link io.permazen.annotation.PermazenType @PermazenType}-annotated Java model classes; however, in the latter
     * case these classes will be otherwise ignored.
     *
     * 

     * In this mode, database objects are represented by {@link io.permazen.core.ObjId}'s and {@code enum} values by
     * {@link io.permazen.core.EnumValue}'s.
     */
    CORE_API(false, true),

    /**
     * Permazen Java mode.
     *
     * 

     * Provides database access through standard Java model objects and transaction access via {@link io.permazen.JTransaction}.
     * Requires and provides a {@link Permazen} instance and its associated Java model classes.
     *
     * 
     * In this mode, database objects are represented by Java model class instances and enum values by corresponding
     * Java model {@link Enum} class instances.
     */
    PERMAZEN(true, true);

    private final boolean hasPermazen;
    private final boolean hasCoreAPI;

    SessionMode(boolean hasPermazen, boolean hasCoreAPI) {
        this.hasPermazen = hasPermazen;
        this.hasCoreAPI = hasCoreAPI;
    }

    /**
     * Determine whether the Permazen Java API (e.g., {@link io.permazen.JTransaction}) based on a {@link Permazen}
     * instance is available in this mode.
     *
     * @return true if the Permazen Java API is available
     */
    public boolean hasPermazen() {
        return this.hasPermazen;
    }

    /**
     * Determine whether the core API (e.g., {@link io.permazen.core.Transaction}) is available in this mode.
     *
     * @return true if the core API is available
     */
    public boolean hasCoreAPI() {
        return this.hasCoreAPI;
    }
}