[英]Using Types.NVARCHAR with oracle JDBC driver to work with Cyrillic chars
I am trying to use the "New Methods for National Character Set Type Data in JDK 1.6" , to get a standard JDBC solution to handle cyrillic chars, but when the execution reaches any line with NVARCHAR type, for instance: 我正在尝试使用“JDK 1.6中的国家字符集类型数据的新方法” ,以获得处理西里尔字符的标准JDBC解决方案,但是当执行到达任何具有NVARCHAR类型的行时,例如:
preparedSelect.setObject(3, "суббота", Types.NVARCHAR);
Then I get this exception: 然后我得到这个例外:
java.sql.SQLException: Invalid column type
at oracle.jdbc.driver.SQLStateMapping.newSQLException(SQLStateMapping.java:70)
at oracle.jdbc.driver.DatabaseError.newSQLException(DatabaseError.java:131)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:197)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:261)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:269)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:490)
at oracle.jdbc.driver.OraclePreparedStatement.setObjectCritical(OraclePreparedStatement.java:7922)
at oracle.jdbc.driver.OraclePreparedStatement.setObjectInternal(OraclePreparedStatement.java:7502)
at oracle.jdbc.driver.OraclePreparedStatement.setObject(OraclePreparedStatement.java:7975)
at oracle.jdbc.driver.OraclePreparedStatementWrapper.setObject(OraclePreparedStatementWrapper.java:222)
I also tried to use setNString() but I get an even more strange exception: 我也尝试使用setNString(),但我得到一个更奇怪的例外:
java.lang.AbstractMethodError: oracle.jdbc.driver.OraclePreparedStatementWrapper.setNString(ILjava/lang/String;)V
If I use java -Doracle.jdbc.defaultNChar=true myApplication with regular Types.VARCHAR, the Russian words are stored correctly. 如果我使用带有常规Types.VARCHAR的java -Doracle.jdbc.defaultNChar = true myApplication,则会正确存储俄语单词。 But using -Doracle.jdbc.defaultNChar=true is not an option since I'm working on a legacy application, I do not have control of running production environment, I'm just writing a component to it.
但是使用-Doracle.jdbc.defaultNChar = true不是一个选项,因为我正在处理遗留应用程序,我无法控制运行生产环境,我只是在编写一个组件。 Furthermore, this "Readme for NChar How-to" states that "This conversion has a substantial performance impact".
此外,这篇“NChar How-to自述文件”指出“这种转换对性能产生了重大影响”。 So setting everything to NChar by default when only less than 1% of my tables needs this conversion in not a smart choice.
因此,默认情况下,只有少于1%的表需要进行此转换而不是智能选择时,将所有内容设置为NChar。
I'm using oracle thin driver and I have ojdbc6.jar and orai18n.jar in my classpath. 我正在使用oracle瘦驱动程序,我的classpath中有ojdbc6.jar和orai18n.jar。
I'm looking for a standard JDBC solution. 我正在寻找标准的JDBC解决方案。 I can not use any methods or constants with "oracle" on them.
我不能在它们上使用任何带有“oracle”的方法或常量。 OraclePreparedStatement is not an option for me.
OraclePreparedStatement对我来说不是一个选项。
I tried using Types.NVARCHAR with MSSQL Server and it runs fine. 我尝试使用Types.NVARCHAR与MSSQL Server,它运行正常。
I found the solution! 我找到了解决方案!
I was using ojdbc 11.2.0.1. 我使用的是ojdbc 11.2.0.1。 When I switched to 11.2.0.2, I could get
setNString()
working properly. 当我切换到11.2.0.2时,我可以使
setNString()
正常工作。 But I'm still getting the same java.sql.SQLException: Invalid column type
if I use setObject()
with Type.NVARCHAR
. 但是我仍然得到相同的
java.sql.SQLException: Invalid column type
如果我使用带有Type.NVARCHAR
setObject()
,则java.sql.SQLException: Invalid column type
。 Shame on you Oracle... 惭愧你甲骨文...
Anyway, the solution: switch to ojdbc 11.2.0.2 无论如何,解决方案:切换到ojdbc 11.2.0.2
I managed to make it work some time ago with the following incantations. 不久之前我设法使用以下咒语使其工作。 These methods are an excerpt from a bigger class.
这些方法是一个更大的类的摘录。
import com.mchange.v2.c3p0.C3P0ProxyStatement;
import oracle.jdbc.OraclePreparedStatement;
static {
try {
SET_FORM_OF_USE_METHOD = OraclePreparedStatement.class.getDeclaredMethod("setFormOfUse", new Class[] { Integer.TYPE, Short.TYPE });
} catch (NoSuchMethodException ex) {
LOG.fatal("Can't find the setFormOfUse method", ex);
throw new ExceptionInInitializerError(ex);
}
}
public void nullSafeSet(PreparedStatement st, Object value, int index, SessionImplementor session) throws SQLException {
if (st instanceof OraclePreparedStatement) {
((OraclePreparedStatement)st).setFormOfUse(index, OraclePreparedStatement.FORM_NCHAR);
} else if (st instanceof C3P0ProxyStatement) {
try {
C3P0ProxyStatement c3p0St = (C3P0ProxyStatement) st;
c3p0St.rawStatementOperation(SET_FORM_OF_USE_METHOD, C3P0ProxyStatement.RAW_STATEMENT, new Object[]{index, OraclePreparedStatement.FORM_NCHAR});
} catch (IllegalAccessException ex) {
throw new UnexpectedException("Error calling setFormOfUse through C3P0", ex);
} catch (IllegalArgumentException ex) {
throw new UnexpectedException("Error calling setFormOfUse through C3P0", ex);
} catch (InvocationTargetException ex) {
throw new UnexpectedException("Error calling setFormOfUse through C3P0", ex);
}
} else {
throw new IllegalArgumentException("Unkown PreparedStatement implementation: " + st.getClass() + ". Maybe an unknown connection pool is hiding the OraclePreparedStatement?");
}
st.setString(index, (String) value);
}
The nullSafeSet method is structured to work directly on OraclePreparedStatement instances, or on C3P0ProxyStatement in case you have the C3P0 connection pool; nullSafeSet方法的结构可直接在OraclePreparedStatement实例上运行,或在C3P0ProxyStatement上运行,以防您拥有C3P0连接池; other options will have to be used in case of different pools.
如果是不同的池,则必须使用其他选项。
This method worked with the ojdbc14.jar from Oracle 10.2.0.4. 此方法适用于Oracle 10.2.0.4中的ojdbc14.jar。
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