[WebLogic/JDBC] Why Doest It Show Different JDBC Driver Version?
1. Overview
JDBC Driver version을 확인하기 위해, ojdbc 파일을 압축해제 하여 직접 확인하거나,
-getversion 명령어 등으로 확인할 수 있다.
이 Driver version을 확인하는데, 상황에 따라 다른 version이 표시되면 왜 그런지 추적해보자.
2. Descriptions
2.1 일반적인 Driver version 확인 방법
일반적으로 다음의 명령어를 통해 표시된다.
1
2
3
java -jar ojdbc6.jar
또는
java -jar ojdbc6.jar -getversion
결과는 아래와 같다.
1
2
$ /sw/jdk/jdk1.8.0_381/bin/java -jar ojdbc6.jar
Oracle 11.2.0.4.0 JDBC 4.0 compiled with JDK6 on Thu_Jul_03_18:17:32_PDT_2014
혹은 ojdbc6.jar 를 Decompile(jd-gui 등을 활용)하면 oracle.jdbc.OracleDatabaseMetaData.class에 Hard coding 된 값을 확인할 수 있다.
1
2
3
4
5
6
7
8
9
10
11
package oracle.jdbc;
...
public class OracleDatabaseMetaData implements AdditionalDatabaseMetaData {
private static String DRIVER_NAME = "Oracle JDBC driver";
private static String DRIVER_VERSION = "11.2.0.4.0";
private static int DRIVER_MAJOR_VERSION = 11;
private static int DRIVER_MINOR_VERSION = 2;
...
즉, 이 value를 단순히 출력하는 것이다.
Hard coding 되어 있으므로 상황에 따라 다른 version을 보여주어서는 안된다.
2.2 다른 Driver version이 확인 되는 경우
JDK 1.8.0_381 Version으로 확인 결과와, JDK 1.7.0_80 Version으로 ojdbc6.jar 의 Driver version 확인 결과가 아래와 같이 보여진다.
1
2
3
4
5
$ /sw/jdk/jdk1.7.0_80/bin/java -jar ojdbc6.jar
Oracle 11.2.0.1.0 JDBC 4.0 compiled with JDK6
$ /sw/jdk/jdk1.8.0_381/bin/java -jar ojdbc6.jar
Oracle 11.2.0.4.0 JDBC 4.0 compiled with JDK6 on Thu_Jul_03_18:17:32_PDT_2014
동일한 ojdbc6.jar 가 각각 11.2.0.1.0 과 11.2.0.4.0 으로 확인된다.
앞서 살펴봤듯이, version은 hard coding 되어 있기 때문에 어떤 환경에서든 다른 version이 확인 되면 안된다.
보통 이러한 경우에는, 한가지 짐작할 수 있는 것이 다른 ojdbcX.jar 가 이미 사전에 CLASSPATH 삽입되어 있는 경우다.
검증을 하기 위해 -verbose:class 옵션으로 추적을 하기 위해 다음을 실행한다.
1
2
$ /sw/jdk/jdk1.7.0_80/bin/java -verbose:class -jar ojdbc6.jar > jdk1.7_verbose_class.txt
$ /sw/jdk/jdk1.8.0_381/bin/java -verbose:class -jar ojdbc6.jar > jdk1.8_verbose_class.txt
두 txt 파일에서 ojdbc jar가 load 된 것을 확인해본다.
jdk1.8_verbose_class.txt 파일에서는 다음처럼 특이점이 없다.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
$ grep -i "ojdbc" jdk1.8_verbose_class.txt
[Loaded oracle.jdbc.driver.OracleDriver from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.OracleDriver from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.OracleDriverExtension from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.OracleDriver$1 from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.ClassRef from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.ClassRef$XMLTypeClassRef from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.ClassRef$Locale from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.ClassRef$LocaleCategoryClassRef from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.DiagnosabilityMXBean from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.OracleDiagnosabilityMBean from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.DatabaseError from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.OracleSQLException from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.SQLStateMapping from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.SQLStateMapping$Tokenizer from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.Message from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.Message11 from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.OracleConnection from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.internal.OracleConnection from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.internal.ClientDataSupport from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.OracleConnectionWrapper from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.OracleConnection from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.PhysicalConnection from file:/tmp/ojdbc6.jar]
[Loaded oracle.jdbc.driver.BuildInfo from file:/tmp/ojdbc6.jar]
jdk1.7_verbose_class.txt 파일에서는 Extension 클래스로더 디렉토리에 예전에 백업해둔 Driver가 있었다.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
$ grep -i "ojdbc" jdk1.7_verbose_class.txt
[Loaded oracle.jdbc.driver.OracleDriver from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.OracleDriver from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.OracleDriverExtension from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.OracleDriver$1 from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.ClassRef from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.DiagnosabilityMXBean from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.OracleDiagnosabilityMBean from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.DatabaseError from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.OracleSQLException from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.net.ns.NetException from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.SQLStateMapping from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.SQLStateMapping$Tokenizer from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.Message from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.driver.Message11 from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.internal.ObjectDataFactory from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.sql.ORADataFactory from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.sql.AnyDataFactory from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.jdbc.internal.ObjectData from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.sql.ORAData from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
[Loaded oracle.sql.TypeDescriptorFactory from file:/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak]
/sw/jdk/jdk1.7.0_80/jre/lib/ext/ojdbc6.jar.bak 파일을 확인해보니 Oracle 11.2.0.1.0 version으로 확인된다.
Extension 클래스로더 부터 class를 찾게 되어 다른 환경(서로 다른 JDK Version)에서 다른 Driver version이 출력된 것처럼 보여진 것이다.
3. References
Why Does It Show Different JDBC Driver Version? (Doc ID 2988932.1)