/*- * See the file LICENSE for redistribution information. * * Copyright (c) 2000,2007 Oracle.  All rights reserved. * * $Id: DataView.java,v 12.6 2007/05/04 00:28:25 mark Exp $ */package com.sleepycat.collections;import com.sleepycat.bind.EntityBinding;import com.sleepycat.bind.EntryBinding;import com.sleepycat.compat.DbCompat;import com.sleepycat.db.CursorConfig;import com.sleepycat.db.Database;import com.sleepycat.db.DatabaseConfig;import com.sleepycat.db.DatabaseEntry;import com.sleepycat.db.DatabaseException;import com.sleepycat.db.Environment;import com.sleepycat.db.JoinConfig;import com.sleepycat.db.OperationStatus;import com.sleepycat.db.SecondaryConfig;import com.sleepycat.db.SecondaryDatabase;import com.sleepycat.db.SecondaryKeyCreator;import com.sleepycat.db.Transaction;import com.sleepycat.util.RuntimeExceptionWrapper;import com.sleepycat.util.keyrange.KeyRange;import com.sleepycat.util.keyrange.KeyRangeException;/** * Represents a Berkeley DB database and adds support for indices, bindings and * key ranges. * * <p>This class defines a view and takes care of reading and updating indices, * calling bindings, constraining access to a key range, etc.</p> * * @author Mark Hayes */final class DataView implements Cloneable {    Database db;    SecondaryDatabase secDb;    CurrentTransaction currentTxn;    KeyRange range;    EntryBinding keyBinding;    EntryBinding valueBinding;    EntityBinding entityBinding;    PrimaryKeyAssigner keyAssigner;    SecondaryKeyCreator secKeyCreator;    CursorConfig cursorConfig;      // Used for all operations via this view    boolean writeAllowed;           // Read-write view    boolean ordered;                // Not a HASH Db    boolean recNumAllowed;          // QUEUE, RECNO, or BTREE-RECNUM Db    boolean recNumAccess;           // recNumAllowed && using a rec num binding    boolean btreeRecNumDb;          // BTREE-RECNUM Db    boolean btreeRecNumAccess;      // recNumAccess && BTREE-RECNUM Db    boolean recNumRenumber;         // RECNO-RENUM Db    boolean keysRenumbered;         // recNumRenumber || btreeRecNumAccess    boolean dupsAllowed;            // Dups configured    boolean dupsOrdered;            // Sorted dups configured    boolean transactional;          // Db is transactional    boolean readUncommittedAllowed; // Read-uncommited is optional in DB-CORE    /*     * If duplicatesView is called, dupsView will be true and dupsKey will be     * the secondary key used as the "single key" range.  dupRange will be set     * as the range of the primary key values if subRange is subsequently     * called, to further narrow the view.     */    DatabaseEntry dupsKey;    boolean dupsView;    KeyRange dupsRange;    /**     * Creates a view for a given database and bindings.  The initial key range     * of the view will be open.     */    DataView(Database database, EntryBinding keyBinding,             EntryBinding valueBinding, EntityBinding entityBinding,             boolean writeAllowed, PrimaryKeyAssigner keyAssigner)        throws IllegalArgumentException {        if (database == null) {            throw new IllegalArgumentException("database is null");        }        db = database;        try {            currentTxn =                CurrentTransaction.getInstanceInternal(db.getEnvironment());            DatabaseConfig dbConfig;            if (db instanceof SecondaryDatabase) {                secDb = (SecondaryDatabase) database;                SecondaryConfig secConfig = secDb.getSecondaryConfig();                secKeyCreator = secConfig.getKeyCreator();                dbConfig = secConfig;            } else {                dbConfig = db.getConfig();            }            ordered = !DbCompat.isTypeHash(dbConfig);            recNumAllowed = DbCompat.isTypeQueue(dbConfig) ||                            DbCompat.isTypeRecno(dbConfig) ||                            DbCompat.getBtreeRecordNumbers(dbConfig);            recNumRenumber = DbCompat.getRenumbering(dbConfig);            dupsAllowed = DbCompat.getSortedDuplicates(dbConfig) ||                          DbCompat.getUnsortedDuplicates(dbConfig);            dupsOrdered = DbCompat.getSortedDuplicates(dbConfig);            transactional = currentTxn.isTxnMode() &&                            dbConfig.getTransactional();            readUncommittedAllowed = DbCompat.getReadUncommitted(dbConfig);            btreeRecNumDb = recNumAllowed && DbCompat.isTypeBtree(dbConfig);            range = new KeyRange(dbConfig.getBtreeComparator());        } catch (DatabaseException e) {            throw new RuntimeExceptionWrapper(e);        }        this.writeAllowed = writeAllowed;        this.keyBinding = keyBinding;        this.valueBinding = valueBinding;        this.entityBinding = entityBinding;        this.keyAssigner = keyAssigner;        cursorConfig = CursorConfig.DEFAULT;        if (valueBinding != null && entityBinding != null)            throw new IllegalArgumentException(                "both valueBinding and entityBinding are non-null");        if (keyBinding instanceof com.sleepycat.bind.RecordNumberBinding) {            if (!recNumAllowed) {                throw new IllegalArgumentException(                    "RecordNumberBinding requires DB_BTREE/DB_RECNUM, " +                    "DB_RECNO, or DB_QUEUE");            }            recNumAccess = true;            if (btreeRecNumDb) {                btreeRecNumAccess = true;            }        }        keysRenumbered = recNumRenumber || btreeRecNumAccess;    }    /**     * Clones the view.     */    private DataView cloneView() {        try {            return (DataView) super.clone();        } catch (CloneNotSupportedException willNeverOccur) {            throw new IllegalStateException();        }    }    /**     * Return a new key-set view derived from this view by setting the     * entity and value binding to null.     *     * @return the derived view.     */    DataView keySetView() {        if (keyBinding == null) {            throw new UnsupportedOperationException("must have keyBinding");        }        DataView view = cloneView();        view.valueBinding = null;        view.entityBinding = null;        return view;    }    /**     * Return a new value-set view derived from this view by setting the     * key binding to null.     *     * @return the derived view.     */    DataView valueSetView() {        if (valueBinding == null && entityBinding == null) {            throw new UnsupportedOperationException(                "must have valueBinding or entityBinding");        }        DataView view = cloneView();        view.keyBinding = null;        return view;    }    /**     * Return a new value-set view for single key range.     *     * @param singleKey the single key value.     *     * @return the derived view.     *     * @throws DatabaseException if a database problem occurs.     *     * @throws KeyRangeException if the specified range is not within the     * current range.     */    DataView valueSetView(Object singleKey)        throws DatabaseException, KeyRangeException {        /*         * Must do subRange before valueSetView since the latter clears the         * key binding needed for the former.         */        KeyRange singleKeyRange = subRange(range, singleKey);        DataView view = valueSetView();        view.range = singleKeyRange;        return view;    }    /**     * Return a new value-set view for key range, optionally changing     * the key binding.     */    DataView subView(Object beginKey, boolean beginInclusive,                     Object endKey, boolean endInclusive,                     EntryBinding keyBinding)        throws DatabaseException, KeyRangeException {        DataView view = cloneView();        view.setRange(beginKey, beginInclusive, endKey, endInclusive);        if (keyBinding != null) view.keyBinding = keyBinding;        return view;    }    /**     * Return a new duplicates view for a given secondary key.     */    DataView duplicatesView(Object secondaryKey,                            EntryBinding primaryKeyBinding)        throws DatabaseException, KeyRangeException {        if (!isSecondary()) {            throw new UnsupportedOperationException                ("Only allowed for maps on secondary databases");        }        if (dupsView) {            throw new IllegalStateException();        }        DataView view = cloneView();        view.range = subRange(view.range, secondaryKey);        view.dupsKey = view.range.getSingleKey();        view.dupsView = true;        view.keyBinding = primaryKeyBinding;        return view;    }    /**     * Returns a new view with a specified cursor configuration.     */    DataView configuredView(CursorConfig config) {        DataView view = cloneView();        view.cursorConfig = (config != null) ?            DbCompat.cloneCursorConfig(config) : CursorConfig.DEFAULT;        return view;    }    /**     * Returns the current transaction for the view or null if the environment     * is non-transactional.     */    CurrentTransaction getCurrentTxn() {        return transactional ? currentTxn : null;    }    /**     * Sets this view's range to a subrange with the given parameters.     */    private void setRange(Object beginKey, boolean beginInclusive,                          Object endKey, boolean endInclusive)        throws DatabaseException, KeyRangeException {        KeyRange useRange = useSubRange();        useRange = subRange            (useRange, beginKey, beginInclusive, endKey, endInclusive);        if (dupsView) {            dupsRange = useRange;        } else {            range = useRange;        }    }    /**     * Returns the key thang for a single key range, or null if a single key     * range is not used.     */    DatabaseEntry getSingleKeyThang() {        return range.getSingleKey();    }    /**     * Returns the environment for the database.     */    final Environment getEnv() {        return currentTxn.getEnvironment();    }    /**     * Returns whether this is a view on a secondary database rather     * than directly on a primary database.     */    final boolean isSecondary() {        return (secDb != null);    }    /**     * Returns whether no records are present in the view.     */    boolean isEmpty()        throws DatabaseException {        DataCursor cursor = new DataCursor(this, false);        try {            return cursor.getFirst(false) != OperationStatus.SUCCESS;        } finally {            cursor.close();        }    }    /**     * Appends a value and returns the new key.  If a key assigner is used     * it assigns the key, otherwise a QUEUE or RECNO database is required.     */    OperationStatus append(Object value, Object[] retPrimaryKey,                           Object[] retValue)        throws DatabaseException {        /*         * Flags will be NOOVERWRITE if used with assigner, or APPEND         * otherwise.