Java 11 All Feature methods

Java 11 Release changes

Java 11 has introduced a lot of additional methods in many classes. Let's see one by one.

Methods in String class

Similar to python methods

String.strip()

String.stripTrailing()

String.stripLeading()

String.lines()

String.repeat(int)

String.isBlank()

Methods in Files class

Files.readString(Path)

Files.writeString

Files.isSameFile

FileReader class changes

new constructors

FileReader(String fileName, Charset charset)

FileReader(File file, Charset charset)

Methods in InputStream

InputStream.nullInputStream

InputStream.readNBytes(int)


Methods in OutputStream:

OutputStream.nullOutputStream

FileWriter class changes

new constructors:

FileWriter(String fileName, Charset charset)

FileWriter(String fileName, Charset charset, boolean append)

FileWriter(File file, Charset charset)

FileWriter(File file, Charset charset, boolean append)

Reader class changes

new methods:
Reader.nullReader

ListSelectionModel class changes

ListSelectionModel.getSelectedIndices

ListSelectionModel.getSelectedItemsCount

ShortBuffer class changes

ShortBuffer.mismatch(ShortBuffer)


more changes will be updated soon

Exception in thread "main" javax.persistence.PersistenceException: org.hibernate.exception.ConstraintViolationException: could not execute statement

The reason of throwing this exception is you are trying to save an object which has an invalid foreign key column value, eg: user_profile table contains user_id column which is a foreign key from user table, so if you are adding a record in to user_profile table with an invalid user_id value then this exception may be thrown. So, the solution is use a valid foreign key column value.

Exception in thread "main" javax.persistence.PersistenceException: org.hibernate.exception.ConstraintViolationException: could not execute statement

at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:147)

at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:155)

at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:162)

at org.hibernate.internal.SessionImpl.doFlush(SessionImpl.java:1434)

at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:484)

at org.hibernate.internal.SessionImpl.flushBeforeTransactionCompletion(SessionImpl.java:3190)

at org.hibernate.internal.SessionImpl.beforeTransactionCompletion(SessionImpl.java:2404)

at org.hibernate.engine.jdbc.internal.JdbcCoordinatorImpl.beforeTransactionCompletion(JdbcCoordinatorImpl.java:467)

at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.beforeCompletionCallback(JdbcResourceLocalTransactionCoordinatorImpl.java:146)

at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.access$100(JdbcResourceLocalTransactionCoordinatorImpl.java:38)

at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl$TransactionDriverControlImpl.commit(JdbcResourceLocalTransactionCoordinatorImpl.java:220)

at org.hibernate.engine.transaction.internal.TransactionImpl.commit(TransactionImpl.java:68)

at com.forensen.webui.Sample.main(Sample.java:38)

Caused by: org.hibernate.exception.ConstraintViolationException: could not execute statement

at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:59)

at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:42)

at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:111)

at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:97)

at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:207)

at org.hibernate.engine.jdbc.batch.internal.NonBatchingBatch.addToBatch(NonBatchingBatch.java:45)

at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:3001)

at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:3501)

at org.hibernate.action.internal.EntityInsertAction.execute(EntityInsertAction.java:89)

at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:586)

at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:460)

at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:337)

at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:39)

at org.hibernate.internal.SessionImpl.doFlush(SessionImpl.java:1428)

... 9 more

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (`webuidb`.`msg_inbox`, CONSTRAINT `msg_inbox_ibfk_1` FOREIGN KEY (`REQUEST_ID`) REFERENCES `msg_outbox` (`REQUEST_ID`))

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:423)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)

at com.mysql.jdbc.Util.getInstance(Util.java:381)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1015)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3558)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3490)

at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1959)

at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2109)

at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2643)

at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2077)

at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2362)

at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2280)

at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2265)

at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:204)

... 18 more

SQL Error: 1064, SQLState: 42000:org.hibernate.exception.SQLGrammarException:

This problem happens when we use any kind of legal word as the name of the table or column. Here, the legal word means a word which is treated by hibernate in a different manner. For instance, if you user the word 'from' as the column name, the same error will occur because the word 'from' is used in the sql (select * from tablename). I advice you to change the column names.

So, it will be better if the reserved keyword is not used as the column name or table name......

One of my favourite java frameworks

Always happy to help you,  my profile in stackoverflow.com.