Java ScalarHandler类代码示例

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
public static boolean migrateOrCreateIfNotExists(String dbname) {
    String dbpath = getDbPath(dbname);
    String jdbcurl = "jdbc:h2:file:" + dbpath + ";DB_CLOSE_ON_EXIT=FALSE";
    LOG.info("new jdbcurl = {}", jdbcurl);
    Connection conn = null;
    try {
        conn = DriverManager.getConnection(jdbcurl, "sa", "");

        DataSource ds = new CustomFlywayDataSource(new PrintWriter(System.out), conn);
        Flyway flyway = new Flyway();
        flyway.setDataSource(ds);
        // explicitly set h2db driver loaded (= including this jar file) class loader
        flyway.setClassLoader(conn.getClass().getClassLoader());
        flyway.migrate();
        LOG.info("db[{}] migration success", dbname);

        // may be already closed -> reconnect.
        DbUtils.closeQuietly(conn);
        conn = DriverManager.getConnection(jdbcurl, "sa", "");

        QueryRunner r = new QueryRunner();
        Long cnt = r.query(conn, "select count(*) from PROXY_HISTORY", new ScalarHandler<Long>());
        LOG.info("db[{}] open/creation success(select count(*) from logtable returns {})", dbname, cnt);

        return true;
    } catch (SQLException e) {
        LOG.error("db[" + dbname + "] open/migrate/creation error", e);
        return false;
    } finally {
        DbUtils.closeQuietly(conn);
    }
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
/**
 * Find a single value based on the given model, from arbitrary SQL, and
 * use the cache.
 *
 * @param model
 * @param sql
 * @param params
 * @param <T>
 * @return
 */
public <T> T cachedScalar(Class model, String sql, Object ...params) {
    String cacheKey = buildCacheKey(model, sql, params);
    T result = (T) SmartQueryCache.getSmart(model.getCanonicalName(), cacheKey);
    if (result != null) {
        return result;
    }
    QueryRunner runner = new QueryRunner(dataSource);
    try {
        result = runner.query(sql, new ScalarHandler<T>(), params);
        SmartQueryCache.set(model.getCanonicalName(), cacheKey, result);
        return result;
    } catch (SQLException e) {
        throw new RuntimeException(e);
    }

}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
public void refillQueue() {
    QueryRunner q = db.newQuery();
    //String sql = "insert into users (username) values (?)";
    String sql = "REPLACE INTO stallion_tickets (ticket_name) VALUES('a')";
    long nextId = 0;
    try {
        nextId = q.insert(sql, new ScalarHandler<Long>());
    } catch (SQLException e) {
        throw new RuntimeException(e);
    }
    Log.fine("Next ticket id {0}", nextId);
    nextId = nextId * 1000;

    //ScalarHandler<Long> scalar = new ScalarHandler<Long>();
    //Long nextId = q.query("SELECT nextval('stallion_tickets_seq')", scalar);
    for (int x= 0; x < 1000; x++ ) {
        loadedIds.add(nextId + x);
    }
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
/**
 *
 * @param database
 * @param sqlList
 * @param parametersList
 * @return
 */
public static List<Long> executeMultipleInserts(MetadataDatabase database, List<String> sqlList, List<Object[]> parametersList) {
    try (Connection conn = database.getConnection()) {
        List<Long> results = new ArrayList<>();
        for (int i = 0; i < sqlList.size(); i++) {
            Object[] parameters = parametersList.get(i);
            String sql = sqlList.get(i);
            
            ResultSetHandler<Long> rsh = new ScalarHandler<>();
            Long id = queryRunner.insert(conn, sql, rsh, parameters);
            results.add(id);
        }
        return results;
    } catch (SQLException e) {
        throw new JVoidDataAccessException(e);
    }
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public Player addPlayer(Player player) {
    try {
        long id = getQueryRunner().insert("INSERT INTO Player (savekey, name, level, experience, lastUpdate, email, supporterLevel, relics, isCheater, lastQuestCreation) VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?);", new ScalarHandler<>(),
                player.getKey(),
                player.getName(),
                player.getLevel(),
                player.getExperience(),
                player.getLastUpdate(),
                player.getEmail(),
                player.getSupporterLevel(),
                player.getRelics(),
                player.isCheater(),
                player.getLastQuestCreation());
        player.setId(id);
        return player;
    } catch (SQLException e) {
        if (e.getErrorCode() == MySqlErrorCode.DUPLICATE_ENTRY) {
            throw new KeyAlreadyExists();
        } else {
            throw new GatewayError("Failed to insert player into database.", e);
        }
    }
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public void addPurchase(Purchase purchase) {
    try {
        getQueryRunner().insert("INSERT INTO PlayerPurchasedProduct (playerId, productId, store, data, signature, appVersion, purchaseDate) VALUES(?, ?, ?, ?, ?, ?, ?);",
                new ScalarHandler<>(),
                purchase.getPlayerId(),
                purchase.getProductId(),
                purchase.getStore(),
                purchase.getData(),
                purchase.getSignature(),
                purchase.getAppVersion(),
                purchase.getPurchaseDate());
    } catch (SQLException e) {
        if (e.getErrorCode() == MySqlErrorCode.DUPLICATE_ENTRY) {
            throw new KeyAlreadyExists();
        } else {
            throw new GatewayError("Failed to create purchase entity.", e);
        }
    }
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public void addFoilCardToPlayer(long playerId, FoilCard foilCard) {
    try {
        int rows = getQueryRunner().update("UPDATE PlayerFoilCard SET amount=amount+? WHERE playerId=? AND cardId=? AND cardType=?;",
                foilCard.getAmount(),
                playerId,
                foilCard.getCardId(),
                foilCard.getCardType());
        if (rows < 1) {
            getQueryRunner().insert("INSERT INTO PlayerFoilCard (playerId, cardId, cardType, amount) VALUES (?, ?, ?, ?);",
                    new ScalarHandler<>(),
                    playerId,
                    foilCard.getCardId(),
                    foilCard.getCardType(),
                    foilCard.getAmount());
        }
    } catch (SQLException e) {
        throw new GatewayError("Failed to add foil card to player.", e);
    }
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
/**
 * 根据表达式统计长度
 *
 * @param example
 * @param classz
 * @param <T>
 * @return
 */
public <T> long countByExample(Example example, Class<T> classz) {
    DBTableMeta dbTableMeta = DBTableMetaFactory.getDBTableMeta(classz);
    AnalyzeResult analyzeResult = getSqlAnalyzer().analyzeCountByExample(dbTableMeta, example);

    printSQL(analyzeResult.getSql(), analyzeResult.getParams());

    Connection conn = getDbConnectionFactory().getConnection();

    QueryRunner queryRunner = new QueryRunner();
    try {
        return queryRunner.query(conn, analyzeResult.getSql(), new ScalarHandler<Long>(1), analyzeResult.getParams());
    } catch (SQLException e) {
        throw new RuntimeException(e);
    } finally {
        getDbConnectionFactory().releaseConnection(conn);
    }
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public <T> Object sumByExample(Example example, Class<T> classz) {
    DBTableMeta dbTableMeta = DBTableMetaFactory.getDBTableMeta(classz);
    AnalyzeResult analyzeResult = getSqlAnalyzer().analyzeSumByExample(dbTableMeta, example);

    printSQL(analyzeResult.getSql(), analyzeResult.getParams());

    Connection conn = getDbConnectionFactory().getConnection();

    QueryRunner queryRunner = new QueryRunner();
    try {
        T result = queryRunner.query(conn, analyzeResult.getSql(), new ScalarHandler<T>(1), analyzeResult.getParams());
        return result == null ? 0D : result;
    } catch (SQLException e) {
        throw new RuntimeException(e);
    } finally {
        getDbConnectionFactory().releaseConnection(conn);
    }
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Test
public void test5() throws SQLException{//ʹ��ArrayHandler()������������࣬����ʹ�����淽�����ؽ����������
	QueryRunner runner=new QueryRunner(JdbcUtils.getDataSource());//ͨ������һ�����ݿ����ӳأ�����һ��dbutils�������Ӳ��������ֶ��ͷţ�dbutils��ܻ�������ͷ�
	String sql="select count(*) from users";
	/*Object res[]=(Object[]) runner.query(sql,new ArrayHandler());
	long totalrecord=(Long) res[0];
	int count=(int)totalrecord;
	System.out.println(count);
	
	int totalrecord=((Long)res[0]).intValue;
	System.out.println(totalrecord);
	*/
	
	int totalrecord=((Long)runner.query(sql, new ScalarHandler(1))).intValue();
	System.out.println(totalrecord);
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public String resolveAlleleList(final String glstring) {
    checkNotNull(glstring);
    checkArgument(!glstring.isEmpty());
    QueryRunner queryRunner = new QueryRunner(dataSource);
    try {
        String id = (String) queryRunner.query(ALLELE_LIST_ID_SQL, new ScalarHandler(), JdbcUtils.hash(glstring));
        if (id != null) {
            return id;
        }
    }
    catch (SQLException e) {
        logger.warn("could not resolve id for allele list with glstring " + abbrev(glstring), e);
    }
    return idSupplier.createAlleleListId();
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public String resolveHaplotype(final String glstring) {
    checkNotNull(glstring);
    checkArgument(!glstring.isEmpty());
    QueryRunner queryRunner = new QueryRunner(dataSource);
    try {
        String id = (String) queryRunner.query(HAPLOTYPE_ID_SQL, new ScalarHandler(), JdbcUtils.hash(glstring));
        if (id != null) {
            return id;
        }
    }
    catch (SQLException e) {
        logger.warn("could not resolve id for haplotype with glstring " + abbrev(glstring), e);
    }
    return idSupplier.createHaplotypeId();
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public String resolveGenotype(final String glstring) {
    checkNotNull(glstring);
    checkArgument(!glstring.isEmpty());
    QueryRunner queryRunner = new QueryRunner(dataSource);
    try {
        String id = (String) queryRunner.query(GENOTYPE_ID_SQL, new ScalarHandler(), JdbcUtils.hash(glstring));
        if (id != null) {
            return id;
        }
    }
    catch (SQLException e) {
        logger.warn("could not resolve id for genotype with glstring " + abbrev(glstring), e);
    }
    return idSupplier.createGenotypeId();
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public String resolveGenotypeList(final String glstring) {
    checkNotNull(glstring);
    checkArgument(!glstring.isEmpty());
    QueryRunner queryRunner = new QueryRunner(dataSource);
    try {
        String id = (String) queryRunner.query(GENOTYPE_LIST_ID_SQL, new ScalarHandler(), JdbcUtils.hash(glstring));
        if (id != null) {
            return id;
        }
    }
    catch (SQLException e) {
        logger.warn("could not resolve id for genotype list with glstring " + abbrev(glstring), e);
    }
    return idSupplier.createGenotypeListId();
}
 

import org.apache.commons.dbutils.handlers.ScalarHandler; //导入依赖的package包/类
@Override
public String resolveMultilocusUnphasedGenotype(final String glstring) {
    checkNotNull(glstring);
    checkArgument(!glstring.isEmpty());
    QueryRunner queryRunner = new QueryRunner(dataSource);
    try {
        String id = (String) queryRunner.query(MULTILOCUS_UNPHASED_GENOTYPE_ID_SQL, new ScalarHandler(), JdbcUtils.hash(glstring));
        if (id != null) {
            return id;
        }
    }
    catch (SQLException e) {
        logger.warn("could not resolve id for multilocus unphased genotype with glstring " + abbrev(glstring), e);
    }
    return idSupplier.createMultilocusUnphasedGenotypeId();
}