com.alibaba.wasp.meta.TestFMetaStore.java Source code

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/**
 * Copyright 2010 The Apache Software Foundation
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 com.alibaba.wasp.meta;

import com.alibaba.wasp.DeserializationException;
import com.alibaba.wasp.EntityGroupInfo;
import com.alibaba.wasp.EntityGroupLocation;
import com.alibaba.wasp.FConstants;
import com.alibaba.wasp.MetaException;
import com.alibaba.wasp.ServerName;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HBaseTestingUtility;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.Pair;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.NavigableMap;
import java.util.Set;
import java.util.TreeMap;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;

public class TestFMetaStore {

    private static final Log LOG = LogFactory.getLog(TestFMetaStore.class);
    private final static HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility();
    private static FMetaStore fMetaService;
    private Configuration conf = HBaseConfiguration.create(TEST_UTIL.getConfiguration());
    private String metaTable = conf.get(FConstants.METASTORE_TABLE, FConstants.DEFAULT_METASTORE_TABLE);

    @BeforeClass
    public static void setUpBeforeClass() throws Exception {
        TEST_UTIL.getConfiguration().setInt("hbase.regionserver.info.port", -1);
        TEST_UTIL.getConfiguration().setInt("hbase.master.info.port", -1);
        TEST_UTIL.startMiniCluster(1);
        Configuration conf = HBaseConfiguration.create(TEST_UTIL.getConfiguration());
        FMetaUtil.checkAndInit(conf);
        fMetaService = new FMetaStore(conf);
        LOG.info("Check and Init FMetaStore");
        fMetaService.connect();
    }

    @AfterClass
    public static void tearDownAfterClass() throws Exception {
        TEST_UTIL.shutdownMiniCluster();
    }

    @Test
    public void testCheckAndInit() throws IOException {
        HBaseAdmin admin = new HBaseAdmin(conf);
        assertTrue(admin.tableExists(metaTable));
        assertTrue(admin.isTableEnabled(metaTable));
        admin.close();
    }

    @Test
    public void testClean() throws IOException {
        boolean success = FMetaUtil.clean(conf);
        assertTrue(success);
        HBaseAdmin admin = new HBaseAdmin(conf);
        assertFalse(admin.tableExists(metaTable));
        admin.close();
        FMetaUtil.checkAndInit(conf);
    }

    @Test
    public void testCreateTable() throws MetaException {
        FTable User = FMetaTestUtil.User;
        FTable Photo = FMetaTestUtil.Photo;
        fMetaService.createTable(User);
        assertTrue(fMetaService.tableExists(User.getTableName()));
        FTable table = fMetaService.getTable(User.getTableName());
        compare(table, User);
        try {
            fMetaService.createTable(User);
            assertTrue(false);
        } catch (MetaException e) {
            assertTrue(true);
        }
        assertTrue(!fMetaService.tableExists(Photo.getTableName()));
        fMetaService.createTable(Photo);
        assertTrue(fMetaService.tableExists(Photo.getTableName()));
        table = fMetaService.getTable(Photo.getTableName());
        compare(table, Photo);
        fMetaService.dropTable(User.getTableName());
        fMetaService.dropTable(Photo.getTableName());
    }

    @Test
    public void testDropTable() throws MetaException {
        FTable User = FMetaTestUtil.User;
        if (fMetaService.tableExists(User.getTableName())) {
            fMetaService.dropTable(User.getTableName());
            assertFalse(fMetaService.tableExists(User.getTableName()));
        } else {
            fMetaService.createTable(User);
            assertTrue(fMetaService.tableExists(User.getTableName()));
            fMetaService.dropTable(User.getTableName());
            assertFalse(fMetaService.tableExists(User.getTableName()));
        }
    }

    @Test
    public void testAlterTable() throws MetaException {
        FTable User = FMetaTestUtil.User;

        if (fMetaService.tableExists(User.getTableName())) {
            fMetaService.dropTable(User.getTableName());
            assertFalse(fMetaService.tableExists(User.getTableName()));
        }
        fMetaService.createTable(User);
        assertTrue(fMetaService.tableExists(User.getTableName()));

        FTable newTable = clone(User);
        newTable.setOwner("ROOT");
        assertFalse(User.getOwner().equals(newTable.getOwner()));

        fMetaService.alterTable(User.getTableName(), newTable);
        FTable newGetTable = fMetaService.getTable(User.getTableName());
        assertFalse(User.getOwner().equals(newGetTable.getOwner()));
        assertTrue(newTable.getOwner().equals(newGetTable.getOwner()));
        fMetaService.dropTable(User.getTableName());
    }

    @Test
    public void testGetAllTables() throws MetaException {
        restoreAndInitFMETA();
        fMetaService.createTable(FMetaTestUtil.User);
        fMetaService.createTable(FMetaTestUtil.Photo);
        List<FTable> allTables = fMetaService.getAllTables();
        assertEquals(allTables.size(), 2);
        fMetaService.dropTable(FMetaTestUtil.User.getTableName());
        fMetaService.dropTable(FMetaTestUtil.Photo.getTableName());
    }

    @Test
    public void testGetChildTables() throws MetaException {
        restoreAndInitFMETA();
        fMetaService.createTable(FMetaTestUtil.User);
        fMetaService.createTable(FMetaTestUtil.Photo);
        List<FTable> childTables = fMetaService.getChildTables(FMetaTestUtil.User.getTableName());
        assertEquals(childTables.size(), 1);
        assertEquals(childTables.get(0).getTableName(), FMetaTestUtil.Photo.getTableName());
        fMetaService.dropTable(FMetaTestUtil.User.getTableName());
        fMetaService.dropTable(FMetaTestUtil.Photo.getTableName());
    }

    @Test
    public void testIndex() throws MetaException {
        FTable Photo = FMetaTestUtil.Photo;
        restoreAndInitFMETA();
        fMetaService.createTable(FMetaTestUtil.User);
        fMetaService.createTable(FMetaTestUtil.Photo);
        // addIndex
        fMetaService.addIndex(Photo.getTableName(), FMetaTestUtil.PhotosByTime);
        fMetaService.addIndex(Photo.getTableName(), FMetaTestUtil.PhotosByTag);
        // getAllIndex
        LinkedHashMap<String, Index> allIndexs = fMetaService.getAllIndex(Photo.getTableName());
        assertEquals(allIndexs.size(), 2);
        // getIndex
        Index PBT = fMetaService.getIndex(Photo.getTableName(), FMetaTestUtil.PhotosByTime.getIndexName());
        compare(PBT, FMetaTestUtil.PhotosByTime);
        // getIndex
        Index PBTAG = fMetaService.getIndex(Photo.getTableName(), FMetaTestUtil.PhotosByTag.getIndexName());
        compare(PBTAG, FMetaTestUtil.PhotosByTag);
        // deleteIndex
        fMetaService.deleteIndex(Photo.getTableName(), FMetaTestUtil.PhotosByTag);
        allIndexs = fMetaService.getAllIndex(Photo.getTableName());
        assertEquals(allIndexs.size(), 1);
        fMetaService.dropTable(FMetaTestUtil.User.getTableName());
        fMetaService.dropTable(FMetaTestUtil.Photo.getTableName());
    }

    @Test
    public void testAddEntityGroup() throws MetaException {
        FTable User = FMetaTestUtil.User;
        String tableName = User.getTableName();
        FTable Photo = FMetaTestUtil.Photo;
        restoreAndInitFMETA();
        fMetaService.createTable(FMetaTestUtil.User);
        fMetaService.createTable(FMetaTestUtil.Photo);

        List<EntityGroupInfo> egis = getEntityGroup(tableName);
        // add EntityGroup
        fMetaService.addEntityGroup(egis);
        // get EntityGroup
        List<EntityGroupInfo> uEgis = fMetaService.getTableEntityGroups(tableName);
        assertEquals(egis.size(), uEgis.size());

        List<EntityGroupInfo> pEgis = fMetaService.getTableEntityGroups(Photo.getTableName());
        assertEquals(pEgis.size(), uEgis.size());

        for (int i = 0; i < pEgis.size(); i++) {
            assertEquals(pEgis.get(i).compareTo(uEgis.get(i)), 0);
        }

        for (EntityGroupInfo egi : uEgis) {
            boolean has = false;
            for (EntityGroupInfo eg : egis) {
                if (egi.equals(eg)) {
                    has = true;
                    break;
                }
            }
            assertTrue(has);
        }
        // test exists
        assertTrue(fMetaService.exists(egis.get(1)));
        fMetaService.deleteEntityGroup(egis.get(1));
        assertFalse(fMetaService.exists(egis.get(1)));

        // delete one EntityGroup
        fMetaService.deleteEntityGroup(egis.get(1));
        uEgis = fMetaService.getTableEntityGroups(tableName);
        assertEquals(egis.size() - 1, uEgis.size());

        fMetaService.deleteEntityGroups(Photo.getTableName());
        uEgis = fMetaService.getTableEntityGroups(tableName);
        assertEquals(egis.size() - 1, uEgis.size());

        // delete all EntityGroup
        fMetaService.deleteEntityGroups(tableName);
        uEgis = fMetaService.getTableEntityGroups(tableName);
        assertEquals(0, uEgis.size());
        fMetaService.dropTable(FMetaTestUtil.User.getTableName());
        fMetaService.dropTable(FMetaTestUtil.Photo.getTableName());
    }

    @Test
    public void testEntityGroup() throws MetaException, DeserializationException {
        FTable User = FMetaTestUtil.User;
        String tableName = User.getTableName();

        restoreAndInitFMETA();
        fMetaService.createTable(FMetaTestUtil.User);

        List<EntityGroupInfo> egis = getEntityGroup(tableName);
        // add EntityGroup
        fMetaService.addEntityGroup(egis);

        for (int i = 0; i < egis.size(); i++) {
            fMetaService.updateEntityGroupLocation(egis.get(i), egLocations[i]);
        }
        for (int i = 0; i < egis.size(); i++) {
            // getEntityGroupLocation
            ServerName sn = fMetaService.getEntityGroupLocation(egis.get(i));
            assertEquals(sn.compareTo(egLocations[i]), 0);
        }

        for (int i = 0; i < egis.size(); i++) {
            // getEntityGroupsAndLocations
            Pair<EntityGroupInfo, ServerName> pair = fMetaService
                    .getEntityGroupAndLocation(egis.get(i).getEntityGroupName());
            assertEquals(pair.getFirst().compareTo(egis.get(i)), 0);
            assertEquals(pair.getSecond().compareTo(egLocations[i]), 0);
        }

        Set<String> disabledTables = new HashSet<String>();
        // fullScan
        Map<EntityGroupInfo, ServerName> entityGroups = fMetaService.fullScan(disabledTables, false);
        assertEquals(entityGroups.size(), egis.size());
        for (int i = 0; i < egis.size(); i++) {
            ServerName sn = entityGroups.get(egis.get(i));
            assertEquals(sn.compareTo(egLocations[i]), 0);
        }

        // getOfflineSplitParents
        Map<EntityGroupInfo, Result> offlineSplitParents = fMetaService.getOfflineSplitParents();
        assertEquals(offlineSplitParents.size(), 0);

        // getServerUserEntityGroups
        NavigableMap<EntityGroupInfo, Result> egR = fMetaService.getServerUserEntityGroups(egLocations[0]);
        assertEquals(1, egR.size());
        {
            Result r = egR.get(egis.get(0));
            byte[] infoValue = r.getValue(FConstants.CATALOG_FAMILY, FConstants.EGINFO);
            byte[] locationValue = r.getValue(FConstants.CATALOG_FAMILY, FConstants.EGLOCATION);
            EntityGroupInfo key = EntityGroupInfo.parseFromOrNull(infoValue);
            ServerName value = ServerName.convert(locationValue);
            assertEquals(key.compareTo(egis.get(0)), 0);
            assertEquals(value.compareTo(egLocations[0]), 0);
        }

        // getTableEntityGroupsAndLocations
        List<Pair<EntityGroupInfo, ServerName>> entityGroupInfos = fMetaService
                .getTableEntityGroupsAndLocations(Bytes.toBytes(tableName), false);
        entityGroups = new TreeMap<EntityGroupInfo, ServerName>();
        for (Pair<EntityGroupInfo, ServerName> pair : entityGroupInfos) {
            entityGroups.put(pair.getFirst(), pair.getSecond());
        }
        for (int i = 0; i < egis.size(); i++) {
            ServerName sn = entityGroups.get(egis.get(i));
            assertEquals(sn.compareTo(egLocations[i]), 0);
        }
        fMetaService.dropTable(FMetaTestUtil.User.getTableName());
    }

    @Test
    public void testFullScan() throws MetaException, DeserializationException {
        FTable User = FMetaTestUtil.User;
        String tableName = User.getTableName();

        List<EntityGroupInfo> egis = getEntityGroup(tableName);
        Map<EntityGroupInfo, ServerName> entityGroups = null;
        restoreAndInitFMETA();
        fMetaService.createTable(FMetaTestUtil.User);
        fMetaService.createTable(FMetaTestUtil.Photo);
        try {
            // add EntityGroup
            fMetaService.addEntityGroup(egis);

            for (int i = 0; i < egis.size(); i++) {
                fMetaService.updateEntityGroupLocation(egis.get(i), egLocations[i]);
            }

            // fullScan
            List<Result> results = fMetaService.fullScan();
            assertEquals(egis.size(), results.size());
            entityGroups = new TreeMap<EntityGroupInfo, ServerName>();
            for (Result r : results) {
                byte[] infoValue = r.getValue(FConstants.CATALOG_FAMILY, FConstants.EGINFO);
                byte[] locationValue = r.getValue(FConstants.CATALOG_FAMILY, FConstants.EGLOCATION);
                EntityGroupInfo key = EntityGroupInfo.parseFromOrNull(infoValue);
                ServerName value = ServerName.convert(locationValue);
                entityGroups.put(key, value);
            }
            for (int i = 0; i < egis.size(); i++) {
                ServerName sn = entityGroups.get(egis.get(i));
                assertEquals(sn.compareTo(egLocations[i]), 0);
            }

            // scanEntityGroupLocation
            byte[] row = Bytes.toBytes("20001");
            EntityGroupLocation egLocation = fMetaService.scanEntityGroupLocation(Bytes.toBytes(tableName), row);
            assertEquals(egLocation.getHostname(), egLocations[2].getHostname());
            assertEquals(egLocation.getPort(), egLocations[2].getPort());
            assertEquals(egLocation.getEntityGroupInfo().compareTo(egis.get(2)), 0);

            row = Bytes.toBytes(1);
            egLocation = fMetaService.scanEntityGroupLocation(Bytes.toBytes(tableName), row);
            assertEquals(egLocation.getHostname(), egLocations[0].getHostname());
            assertEquals(egLocation.getPort(), egLocations[0].getPort());
            assertEquals(egLocation.getEntityGroupInfo().compareTo(egis.get(0)), 0);

            List<EntityGroupLocation> egls = fMetaService.getEntityGroupLocations(Bytes.toBytes(tableName));
            assertEquals(egis.size(), egls.size());

            for (EntityGroupLocation egl : egls) {
                EntityGroupInfo eginfo = egl.getEntityGroupInfo();
                for (int i = 0; i < egis.size(); i++) {
                    if (eginfo.compareTo(egis.get(i)) == 0) {
                        assertEquals(egl.getHostname(), egLocations[i].getHostname());
                        assertEquals(egl.getPort(), egLocations[i].getPort());
                        break;
                    }
                }
            }
        } finally {
            fMetaService.dropTable(FMetaTestUtil.User.getTableName());
            fMetaService.dropTable(FMetaTestUtil.Photo.getTableName());
        }
    }

    @Test
    public void testModifyEntityGroup() throws MetaException {
        FTable User = FMetaTestUtil.User;
        String tableName = User.getTableName();

        List<EntityGroupInfo> egis = getEntityGroup(tableName);
        restoreAndInitFMETA();
        fMetaService.createTable(FMetaTestUtil.User);
        // add EntityGroup
        fMetaService.addEntityGroup(egis);

        for (int i = 0; i < egis.size(); i++) {
            fMetaService.updateEntityGroupLocation(egis.get(i), egLocations[i]);
        }
        EntityGroupInfo egi = egis.get(1);
        assertFalse(egi.isOffline());
        egi.setOffline(true);
        fMetaService.modifyEntityGroupInfo(egi);

        EntityGroupInfo egi2 = fMetaService.getEntityGroupInfo(egi);
        assertEquals(egi.compareTo(egi2), 0);
        fMetaService.dropTable(FMetaTestUtil.User.getTableName());
    }

    @Test
    public void testIsTableAvailable() throws IOException {
        FTable User = FMetaTestUtil.User;
        String tableName = User.getTableName();

        List<EntityGroupInfo> egis = getEntityGroup(tableName);
        restoreAndInitFMETA();
        fMetaService.createTable(FMetaTestUtil.User);
        // add EntityGroup
        fMetaService.addEntityGroup(egis);

        for (int i = 0; i < egis.size(); i++) {
            fMetaService.updateEntityGroupLocation(egis.get(i), egLocations[i]);
        }
        boolean isTableAvailable = fMetaService.isTableAvailable(Bytes.toBytes(tableName));
        assertTrue(isTableAvailable);
        fMetaService.dropTable(FMetaTestUtil.User.getTableName());
    }

    public void restoreAndInitFMETA() throws MetaException {
        boolean success = FMetaUtil.clean(conf);
        assertTrue(success);
        FMetaUtil.checkAndInit(conf);
    }

    public static List<EntityGroupInfo> getEntityGroup(String tableName) {
        byte[][] splitKeys = { null, Bytes.toBytes("10000"), Bytes.toBytes("20000"), Bytes.toBytes("30000"),
                Bytes.toBytes("40000"), Bytes.toBytes("50000"), Bytes.toBytes("60000"), Bytes.toBytes("70000"),
                Bytes.toBytes("80000"), Bytes.toBytes("90000"), null };
        List<EntityGroupInfo> egis = new ArrayList<EntityGroupInfo>();
        for (int i = 0; i < splitKeys.length - 2; i++) {
            EntityGroupInfo egi = new EntityGroupInfo(Bytes.toBytes(tableName), splitKeys[i], splitKeys[i + 1]);
            egis.add(egi);
        }
        return egis;
    }

    ServerName[] egLocations = { new ServerName("host1", 100, 1000), new ServerName("host2", 100, 1000),
            new ServerName("host3", 100, 1000), new ServerName("host4", 100, 1000),
            new ServerName("host5", 100, 1000), new ServerName("host6", 100, 1000),
            new ServerName("host7", 100, 1000), new ServerName("host8", 100, 1000),
            new ServerName("host9", 100, 1000), new ServerName("host10", 100, 1000) };

    public static FTable clone(FTable table) {
        FTable clone = new FTable();
        clone.setTableName(table.getTableName());
        clone.setOwner(table.getOwner());
        clone.setCreateTime(table.getCreateTime());
        clone.setLastAccessTime(table.getLastAccessTime());
        clone.setColumns(clone(table.getColumns()));
        clone.setPrimaryKeys(clone(table.getPrimaryKeys()));
        clone.setTableType(table.getTableType());
        clone.setEntityGroupKey(clone(table.getEntityGroupKey()));
        clone.setParentName(table.getParentName());
        return clone;
    }

    public static Field clone(Field field) {
        if (field == null) {
            return null;
        }
        Field clone = new Field();
        clone.setComment(field.getComment());
        clone.setFamily(field.getFamily());
        clone.setKeyWord(field.getKeyWord());
        clone.setName(field.getName());
        clone.setType(field.getType());
        return clone;
    }

    public static Map<String, String> clone(Map<String, String> parameters) {
        Map<String, String> clone = new HashMap<String, String>();
        clone.putAll(parameters);
        return clone;
    }

    public static LinkedHashMap<String, Field> clone(LinkedHashMap<String, Field> fields) {
        if (fields == null) {
            return null;
        }

        LinkedHashMap<String, Field> clone = new LinkedHashMap<String, Field>();
        for (Field field : fields.values()) {
            Field cloneField = clone(field);
            clone.put(cloneField.getName(), cloneField);
        }
        return clone;
    }

    public static void compare(FTable left, FTable right) {
        if (compareNull(left, right)) {
            assertTrue(false);
            return;
        }
        if (left != null && right != null) {
            assertTrue(left.getTableName().equals(right.getTableName()));
            assertTrue(left.getOwner().equals(right.getOwner()));
            assertTrue(left.getCreateTime() == right.getCreateTime());
            assertTrue(left.getLastAccessTime() == right.getLastAccessTime());
            assertTrue(left.getTableType().equals(right.getTableType()));
            compare(left.getColumns(), right.getColumns());
            compare(left.getPrimaryKeys(), right.getPrimaryKeys());
            assertTrue(left.getTableType().equals(right.getTableType()));
            compare(left.getEntityGroupKey(), right.getEntityGroupKey());
            compare(left.getParentName(), right.getParentName());
            compare(left.getParameters(), right.getParameters());
        }
    }

    public static void compare(LinkedHashMap<String, Field> left, LinkedHashMap<String, Field> right) {
        if (compareNull(left, right)) {
            assertTrue(false);
            return;
        }
        if (left != null && right != null) {
            assertTrue(left.size() == right.size());
            Iterator<Entry<String, Field>> leftIter = left.entrySet().iterator();
            Iterator<Entry<String, Field>> rightIter = right.entrySet().iterator();
            while (leftIter.hasNext()) {
                Field leftField = leftIter.next().getValue();
                Field rightField = rightIter.next().getValue();
                compare(rightField, leftField);
            }
        }
    }

    public static void compare(Field left, Field right) {
        if (compareNull(left, right)) {
            assertTrue(false);
            return;
        }
        if (left != null && right != null) {
            assertTrue(left.getKeyWord().equals(right.getKeyWord()));
            assertTrue(left.getName().equals(right.getName()));
            assertTrue(left.getFamily().equals(right.getFamily()));
            assertTrue(left.getType().equals(right.getType()));
            compare(left.getComment(), right.getComment());
        }
    }

    public static void compare(Map<String, String> left, Map<String, String> right) {
        if (compareNull(left, right)) {
            return;
        }
        if (left != null && right != null) {
            assertTrue(left.size() == right.size());
            Iterator<Entry<String, String>> iter = left.entrySet().iterator();
            while (iter.hasNext()) {
                Entry<String, String> entry = (Entry<String, String>) iter.next();
                String key = entry.getKey();
                String leftVal = entry.getValue();
                String rightVal = right.get(key);
                compare(leftVal, rightVal);
            }
        }
    }

    public static void compare(String left, String right) {
        if (compareNull(left, right)) {
            return;
        }
        if (left != null && right != null) {
            assertTrue(left.equals(right));
        }
    }

    public static void compare(Index left, Index right) {
        if (compareNull(left, right)) {
            assertTrue(false);
            return;
        }
        if (left != null && right != null) {
            assertTrue(left.getIndexName().equals(right.getIndexName()));
            compare(left.getIndexKeys(), right.getIndexKeys());
            compare(left.getParameters(), right.getParameters());
        }
    }

    public static boolean compareNull(Object left, Object right) {
        if (left == null && right == null) {
            return true;
        }
        if (left == null && right != null) {
            return false;
        }
        if (left != null && right == null) {
            return false;
        }
        return false;
    }
}