Hi Robert,
I had a chance to look at the code you provided and part of the problem is that
MyDriver is not adhering to the JDBC specification as the call to
registerDriver *must* be in the static block of the java.sql.Driver
implementation and *not* in the constructor. The registerWithDriverManager()
logic and the fact the call to this method is in the constructor is the primary
culprit.
I will probably put back the static block at least in the short term but please
work with the vendor to address their issue
Best,
Lance
On Apr 3, 2015, at 5:33 AM, Robert Gibson <robbiexgib...@yahoo.com> wrote:
> Hi there,
>
> We are doing some early testing with JDK 9 and have discovered that the
> changes made to java.sql.DriverManager back in November/December have
> introduced an incompatibility with our JDBC driver (that we have used
> unchanged since Java 6) when it is pre-loaded with Class.forName (as
> recommended by Tomcat and specified as being harmless in the JavaDoc). We
> filed a bug report but it got an incident ID JI-9019539 and then disappeared
> into a black hole.
>
> In the hope of the problem getting a bit more attention I attach a
> reproducible test case that is representative of the commercially-available
> JDBC driver that we use (hint: the name rhymes with MyFace and it's used in a
> lot of banks). I guess the problem is that the driver is calling
> DriverManager.getDrivers() as part of its registration process, which is now
> causing the stack overflow given at the end of this mail, after the code.
>
> If you compile the attached files into test.jar and run
> java -cp test.jar JDBCTest n
> java -cp test.jar JDBCTest y
> then the test should print
> Trying to connect to jdbc:mydriver
> OK
> in both cases (as it does with Java 8).
> When running with Java 9, the second command prints
> Trying to connect to jdbc:mydriver
> FAIL
> No suitable driver found for jdbc:mydriver
>
> Hope this is helpful.
> Regards,
> Robert
>
> JDBCTest.java
>
> import java.io.*;
> import java.sql.*;
> import java.util.*;
>
> public class JDBCTest
> {
> public static void main(String... argv) throws Exception
> {
> if (argv.length > 1) DriverManager.setLogWriter(new
> PrintWriter(System.out));
> String[] urls = new String[] {"jdbc:mydriver"};
> if (argv.length > 0 && argv[0].equals("y")) {
> loadClass("MyDriver");
> }
> for (String url : urls) {
> System.out.println("Trying to connect to " + url);
> try {
> Connection c = DriverManager.getConnection (url);
> if (c == null) System.out.println("FAIL");
> else System.out.println("OK");
> }catch(SQLException e) {
> System.out.println("FAIL");
> System.out.println(e.getMessage());
> }
> }
> }
>
> public static void loadClass(String classname) {
> try { Class.forName(classname); } catch(ClassNotFoundException e) {
> System.out.println("Class not found: " + classname); }
> }
> }
>
> MyDriver.java
>
> import java.sql.*;
> import java.util.Enumeration;
> import java.util.Properties;
> import java.util.logging.Logger;
>
> public class MyDriver implements java.sql.Driver {
> static {
> new MyDriver();
> }
> public MyDriver() {
> this.registerWithDriverManager();
> }
> public final Connection connect(String url, Properties props) throws
> SQLException {
> return acceptsURL(url) ? new MyConnection() : null;
> }
> public boolean acceptsURL(String url) throws SQLException {
> return url.startsWith("jdbc:mydriver");
> }
> public DriverPropertyInfo[] getPropertyInfo(String var1, Properties props)
> throws SQLException {
> return null;
> }
> public int getMajorVersion() {
> return 0;
> }
> public int getMinorVersion() {
> return 1;
> }
> public boolean jdbcCompliant() {
> return false;
> }
> public Logger getParentLogger() throws SQLFeatureNotSupportedException {
> throw new SQLFeatureNotSupportedException("No logging for you");
> }
> protected void registerWithDriverManager() {
> try {
> synchronized(DriverManager.class) {
> DriverManager.registerDriver(this);
> Enumeration e = DriverManager.getDrivers();
> while(e.hasMoreElements()) {
> Driver d = (Driver)e.nextElement();
> if(d instanceof MyDriver && d != this) {
> DriverManager.deregisterDriver(d);
> }
> }
> }
> } catch (SQLException ex) {
> }
> }
> }
>
> MyConnection.java
>
> import java.sql.*;
> import java.util.Map;
> import java.util.Properties;
> import java.util.concurrent.Executor;
>
> public class MyConnection implements Connection {
> @Override
> public Statement createStatement() throws SQLException {
> return null;
> }
> @Override
> public PreparedStatement prepareStatement(String sql) throws SQLException {
> return null;
> }
> @Override
> public CallableStatement prepareCall(String sql) throws SQLException {
> return null;
> }
> @Override
> public String nativeSQL(String sql) throws SQLException {
> return null;
> }
> @Override
> public void setAutoCommit(boolean autoCommit) throws SQLException {
> }
> @Override
> public boolean getAutoCommit() throws SQLException {
> return false;
> }
> @Override
> public void commit() throws SQLException {
> }
> @Override
> public void rollback() throws SQLException {
> }
> @Override
> public void close() throws SQLException {
> }
> @Override
> public boolean isClosed() throws SQLException {
> return false;
> }
> @Override
> public DatabaseMetaData getMetaData() throws SQLException {
> return null;
> }
> @Override
> public void setReadOnly(boolean readOnly) throws SQLException {
> }
> @Override
> public boolean isReadOnly() throws SQLException {
> return false;
> }
> @Override
> public void setCatalog(String catalog) throws SQLException {
> }
> @Override
> public String getCatalog() throws SQLException {
> return null;
> }
> @Override
> public void setTransactionIsolation(int level) throws SQLException {
> }
> @Override
> public int getTransactionIsolation() throws SQLException {
> return 0;
> }
> @Override
> public SQLWarning getWarnings() throws SQLException {
> return null;
> }
> @Override
> public void clearWarnings() throws SQLException {
> }
> @Override
> public Statement createStatement(int resultSetType, int
> resultSetConcurrency) throws SQLException {
> return null;
> }
> @Override
> public PreparedStatement prepareStatement(String sql, int resultSetType,
> int resultSetConcurrency) throws SQLException {
> return null;
> }
> @Override
> public CallableStatement prepareCall(String sql, int resultSetType, int
> resultSetConcurrency) throws SQLException {
> return null;
> }
> @Override
> public Map<String, Class<?>> getTypeMap() throws SQLException {
> return null;
> }
> @Override
> public void setTypeMap(Map<String, Class<?>> map) throws SQLException {
> }
> @Override
> public void setHoldability(int holdability) throws SQLException {
> }
> @Override
> public int getHoldability() throws SQLException {
> return 0;
> }
> @Override
> public Savepoint setSavepoint() throws SQLException {
> return null;
> }
> @Override
> public Savepoint setSavepoint(String name) throws SQLException {
> return null;
> }
> @Override
> public void rollback(Savepoint savepoint) throws SQLException {
> }
> @Override
> public void releaseSavepoint(Savepoint savepoint) throws SQLException {
> }
> @Override
> public Statement createStatement(int resultSetType, int
> resultSetConcurrency, int resultSetHoldability) throws SQLException {
> return null;
> }
> @Override
> public PreparedStatement prepareStatement(String sql, int resultSetType,
> int resultSetConcurrency, int resultSetHoldability) throws SQLException {
> return null;
> }
> @Override
> public CallableStatement prepareCall(String sql, int resultSetType, int
> resultSetConcurrency, int resultSetHoldability) throws SQLException {
> return null;
> }
> @Override
> public PreparedStatement prepareStatement(String sql, int
> autoGeneratedKeys) throws SQLException {
> return null;
> }
> @Override
> public PreparedStatement prepareStatement(String sql, int[] columnIndexes)
> throws SQLException {
> return null;
> }
> @Override
> public PreparedStatement prepareStatement(String sql, String[]
> columnNames) throws SQLException {
> return null;
> }
> @Override
> public Clob createClob() throws SQLException {
> return null;
> }
> @Override
> public Blob createBlob() throws SQLException {
> return null;
> }
> @Override
> public NClob createNClob() throws SQLException {
> return null;
> }
> @Override
> public SQLXML createSQLXML() throws SQLException {
> return null;
> }
> @Override
> public boolean isValid(int timeout) throws SQLException {
> return false;
> }
> @Override
> public void setClientInfo(String name, String value) throws
> SQLClientInfoException {
> }
> @Override
> public void setClientInfo(Properties properties) throws
> SQLClientInfoException {
> }
> @Override
> public String getClientInfo(String name) throws SQLException {
> return null;
> }
> @Override
> public Properties getClientInfo() throws SQLException {
> return null;
> }
> @Override
> public Array createArrayOf(String typeName, Object[] elements) throws
> SQLException {
> return null;
> }
> @Override
> public Struct createStruct(String typeName, Object[] attributes) throws
> SQLException {
> return null;
> }
> @Override
> public void setSchema(String schema) throws SQLException {
> }
> @Override
> public String getSchema() throws SQLException {
> return null;
> }
> @Override
> public void abort(Executor executor) throws SQLException {
> }
> @Override
> public void setNetworkTimeout(Executor executor, int milliseconds) throws
> SQLException {
> }
> @Override
> public int getNetworkTimeout() throws SQLException {
> return 0;
> }
> @Override
> public <T> T unwrap(Class<T> iface) throws SQLException {
> return null;
> }
> @Override
> public boolean isWrapperFor(Class<?> iface) throws SQLException {
> return false;
> }
> }
>
> Stack overflow (recursive call to new MyDriver())
>
> [1] MyDriver.registerWithDriverManager (MyDriver.java:47)
> [2] MyDriver.<init> (MyDriver.java:12)
> [3] sun.reflect.NativeConstructorAccessorImpl.newInstance0 (native method)
> [4] sun.reflect.NativeConstructorAccessorImpl.newInstance
> (NativeConstructorAccessorImpl.java:62)
> [5] sun.reflect.DelegatingConstructorAccessorImpl.newInstance
> (DelegatingConstructorAccessorImpl.java:45)
> [6] java.lang.reflect.Constructor.newInstance (Constructor.java:425)
> [7] java.lang.Class.newInstance (Class.java:464)
> [8] java.util.ServiceLoader$LazyIterator.nextService (ServiceLoader.java:378)
> [9] java.util.ServiceLoader$LazyIterator.next (ServiceLoader.java:402)
> [10] java.util.ServiceLoader$1.next (ServiceLoader.java:478)
> [11] java.sql.DriverManager$2.run (DriverManager.java:614)
> [12] java.sql.DriverManager$2.run (DriverManager.java:594)
> [13] java.security.AccessController.doPrivileged (native method)
> [14] java.sql.DriverManager.ensureDriversInitialized (DriverManager.java:594)
> [15] java.sql.DriverManager.getDrivers (DriverManager.java:437)
> [16] MyDriver.registerWithDriverManager (MyDriver.java:47)
> [17] MyDriver.<init> (MyDriver.java:12)
> [18] MyDriver.<clinit> (MyDriver.java:8)
> [19] java.lang.Class.forName0 (native method)
> [20] java.lang.Class.forName (Class.java:286)
> [21] JDBCTest.loadClass (JDBCTest.java:28)
> [22] JDBCTest.main (JDBCTest.java:12)
Lance Andersen| Principal Member of Technical Staff | +1.781.442.2037
Oracle Java Engineering
1 Network Drive
Burlington, MA 01803
lance.ander...@oracle.com
