Common Jdbc Issues

Common Jdbc Issues-1).

If you get the following Error:

01	<BEA-149205> <Failed to initialize the application ‘TestDataSource’ due to error weblogic.application.ModuleException: .

02	weblogic.application.ModuleException:

03	at weblogic.jdbc.module.JDBCModule.prepare(JDBCModule.java:289)

04	at weblogic.application.internal.flow.ModuleListenerInvoker.prepare(ModuleListenerInvoker.java:93)

05	at weblogic.application.internal.flow.DeploymentCallbackFlow$1.next(DeploymentCallbackFlow.java:387)

06

.

07

.

08	weblogic.common.ResourceException: Could not create pool connection. The DBMS driver exception was: The Network Adapter could not establish the connection

09	- – - – - – or - – - – - -

10	weblogic.common.ResourceException: weblogic.common.ResourceException: Could not create pool connection. The DBMS driver exception was: Io exception: The Network Adapter

Degugging the root Cause of above Issue:
The Above Exception: java.io.IOException: The Network Adapter could not establish the connection
It simply suggest that the Database URL may not be correct in the DataSource XML file locatied inside “<DOMAIN_HOME>\config\jdbc” directoryor may be the TNS name OR some n/w issue between WLS BOX and the DB Box. Please try the following to Double Check it.
Step1). Add JDBC Driver also in the Classpath or Better run “. ./setWLSEnv.sh”
(NOTE: While running the above script please use two DOTs like mentioned above. The first DOT represents that set the Environment in the Current Shell and the second DOT (./) Slash represents that pick up the Script from the current Location. Both DOTs are separated by a single space. Once u run “. ./setWLSEnv.sh” after that try to echo the values of $CLASSPATH and $PATH to make sure that the env is set properly)
Step2). Use WLS   dbping utility to test the Database Network Connectivity from the WebLogic Server Box:
Syntax:
java -classpath /bea103/wl_server103/server/lib/weblogic.jar utils.dbping ORACLE_THIN <dbUserName> <dbPasswoes> <dbURL>

java -classpath $WLSHOME/server/lib/weblogic.jar utils.dbping ORACLE_THIN SOA_SOAINFRA password 10.15.35.0:1525/SID14

Example:
java -classpath /bea103/wl_server103/server/lib/weblogic.jar utils.dbping ORACLE_THIN scott tiger databaseHostName:1521:P15215h
Step 3). Try doing a telnet to connect to the Database Box on the Database Listen Port like following Just to make sure that the Database has started listening on the Mentioned Listen Port or Not …..:
telnet   databaseHostName   1521
————————————————————————–

Common Jdbc Issues-2).

Many times we see that DataSource configured on WebLogic Server was running fine sometimes back and suddenly we start seeing the following Error:

1	Caused by: java.sql.SQLException: Io exception: Got minus one from a read call

2	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)

3	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:146)

4	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:255)

5	at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:387)

6	at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:420)

Degugging the root Cause of above Issue:
The error “Caused by: java.sql.SQLException: Io exception: Got minus one from a read call” clearly indicates the root cause of this issue. “We get the following error “Got minus one from a read call” if the Database goes under Maintenance…..or Database is in inconsistent State (Due to any reason like Database Maintenance or Database unmounting…etc ).
WLS is asking a JDBC driver for a connection and getting that exception, which means the DBMS or network dropped the socket during the driver-DBMS handshake.
The above error ensures that there is Nothing Wrong from WebLogic Side …we need to contact the Database Administrator only.
Step1). Open the Server Log and check the timestamp of the first occurance of that Error in the Server log.
Step2). Confirm with the Database Administrator…. What was the activity happening on the Database side at that time (90% cases u will find that the Database might be under Maintenance that time)

——-Make Use of Appropriate Debug Flags:———

-Dweblogic.resourcepool.max_test_wait_secs=xx
Where xx is the amount of time, in seconds, WebLogic Server waits for connection test before considering the connection test failed. By default, a server instance is assigned a value of 10 seconds. This command line flag manages failures, such as a DBMS network failure, which can cause connection tests and applications to hang for extended periods of time (for example, 10 minutes). If the assigned time period expires, the server instance purges and disables the pool (closes all connections and blocks further reserve attempts) and re-enables the pool as soon as it is possible to reconnect.
You can use the following Debug Flags:
-Dweblogic.debug.DebugJDBCSQL=true
-Dweblogic.log.StdoutSeverity=Debug
Use the Following WLST Script to Enable the JDBC related Debug Flags
“ExampleDebugJdbc.py”
—————————————————————–
user=’weblogic’
password=’weblogic’
url=’t3://localhost:7001′
connect(user, password, url)
edit()
cd(‘Servers/TestServer/ServerDebug/TestServer’)
startEdit()
set(‘DebugJDBCSQL’,'true’)
save()
activate()
—————————————————————–

Common Jdbc Issues-3).

If you see that the Database is going into DataSource is moving to SUSPENDED/Disabled State….The first of all check the database connectivity. If the dfatabase connectivity is OK and WLS is able to establish the Connectivity with the database Successfully then Please try to use the “weblogic.Admin” utility to Restore (Resume) the DataSource.
You can use “weblogic.Admin” utility to Enable and Disable the Pool (DataSource) Just to Confirm whether the dataSource is actually active or not:
Step1). run “. ./setWLSEnv.sh” first in the same Shell prompt….then do the following:
Step2). To suspend:
java weblogic.Admin -url t3://localhost:7001 -username weblogic -password weblogic SUSPEND_POOL YourDataSourceName
Step3). To re-enable:
java weblogic.Admin -url t3://localhost:7001 -username weblogic -password weblogic RESUME_POOL YourDataSourceName
To test whether you are getting any Exception or Error while doing this….If yes u are getting any Error or exception then It means there May be some Database connectivity issue…
If a datasource gets destroyed then even if u are having DataSource Configuration Entries in the “config.xml” and the “<DOMAIN_HOME>/config/jdbc/*.xml” files …still u wont be able to see that datasource in the Monitoring Tab in the AdminConsole. Because as soon as the datasource gets destroyed (Due to N/W disconnect or someother reason) the MBean Object gets destroyed.

Common Jdbc Issues-4).

1	<Warning> <JDBC> <BEA-001153> <Forcibly releasing inactive connection

2	“weblogic.jdbc.wrapper.PoolConnection_oracle_jdbc_driver_T4CConnection@3″ back into the connection pool “TestDataSource”, currently reserved by: java.lang.Exception

3	at weblogic.jdbc.common.internal.ConnectionEnv.setup(ConnectionEnv.java:291)

4	at weblogic.common.resourcepool.ResourcePoolImpl.reserveResource(ResourcePoolImpl.java:314)

5	at weblogic.common.resourcepool.ResourcePoolImpl.reserveResource(ResourcePoolImpl.java:292)

6	at weblogic.jdbc.common.internal.ConnectionPool.reserve(ConnectionPool.java:425)

7	at weblogic.jdbc.common.internal.ConnectionPool.reserve(ConnectionPool.java:316)

If we see above kind of exceptions in our Server Logs then definately we need to look into the Application Code.  “That is either your application reserving and Hholding the jdbc connections (they aren’t lost means leaked), or maybe they are hanging waiting for the DBMS to respond.”
Usually we see this Warning When the Application code obtains a JDBC connection from the WLS datasource, then not using it and not closing it, Means Just Holding the Connection Reference, for longer than your datasource/pool is configured to allow (IdleConnectionTimeout). Make sure that u close all the JDBC related Objects in a proper sequence. like exactly in the following  Order…Always close the ResultSet, Statement and Connection objects insode the finally{} Block in the following order:

1

finally {

2	try {resultset.close();}

3	catch (Exception rse) {}

4	try {statement.close();}

5	catch (Exception sse) {}

6	try {connection.close();

7	catch (Exception cse) {}

8

}

Common Jdbc Issues-5).

Many times we get the following kind of error/exception while using a Connection object:

01	java.sql.SQLException: Closed Connection

02	at oracle.jdbc.driver.SQLStateMapping.newSQLException(SQLStateMapping.java:70)

03	at oracle.jdbc.driver.DatabaseError.newSQLException(DatabaseError.java:133)

04	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:199)

05	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:263)

06	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:271)

07	at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:445)

08	at oracle.jdbc.driver.OracleStatement.ensureOpen(OracleStatement.java:3620)

09	at oracle.jdbc.driver.OracleCallableStatement.execute(OracleCallableStatement.java:3853)

10	at oracle.jdbc.driver.OraclePreparedStatementWrapper.execute(OraclePreparedStatementWrapper.java:1374)

11	at weblogic.jdbc.wrapper.PreparedStatement.execute(PreparedStatement.java:99)

In these cases we need to make sure that you enable the “Test Connection On Reserve” is disabled. for your Connection Pool.This is the best way the pool can ensure That connection pool provides us a good connection when an application ask for it.
Also provide a simple SQL query for connection testing in the DataSource configuration like ‘SELECT * FROM DUAL’

Common Jdbc Issues-6).

If you get the following Error:

01	java.sql.SQLException: No more data to read from socket

02	at oracle.jdbc.driver.T4CMAREngine.unmarshalUB1(T4CMAREngine.java:1200)

03	at oracle.jdbc.driver.T4CMAREngine.unmarshalSB1(T4CMAREngine.java:1155)

04	at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:279)

05	at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:186)

06	at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:521)

07	at oracle.jdbc.driver.T4CStatement.doOall8(T4CStatement.java:194)

08	at oracle.jdbc.driver.T4CStatement.executeForDescribe(T4CStatement.java:853)

09	at oracle.jdbc.driver.OracleStatement.executeMaybeDescribe(OracleStatement.java:1145)

10	at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1267)

11	at oracle.jdbc.driver.OracleStatement.executeInternal(OracleStatement.java:1882)

12	at oracle.jdbc.driver.OracleStatement.execute(OracleStatement.java:1847)

13	at oracle.jdbc.driver.OracleStatementWrapper.execute(OracleStatementWrapper.java:301)

This error occurs if an applications that uses a database connections from the DataSource/Pool and When the application checked out a connection that has been already “timed out” or has been “staled”, still the application uses it to connect to the database, this error occurs.
In this case eother we need to start the Oracle Database Server or the Application Server which is maintaining the Connection Pool (Reseting the DataSource is also a valid option) sothat the staled connection should be cleared out and a new connection should be establised automatically.

Weblogic Graceful shutdown options

Abnormal JVM termination can cause resources such as sockets or segments to lock. Killing or terminating WebLogic Server process from the operating system is considered as abnormal termination. This action might leave .lok files and would not let servers to come up some times. 


Nodemanage may start the server immediately if we kill the process so ensure you kill corresponding nodemanager before killing any managed server JVM processes underneath it



WebLogic Server can be gracefully shutdown by:

• Using administration Console 'Graceful Shutdown" hyperlink
• Using weblogic.Admin SHUTDOWN… command
• Using JMX by invoking stop method on ServerMBean class

Tips

1. To shut down the production server gracefully, use the WebLogic admin console or the weblogic.Admin utility.
2. Graceful shutdown does not abnormally terminate user sessions; it waits for HTTP sessions to complete or time out.
3. WebLogic server can also be configured not to wait (ignore Session During Shutdown option).
4. The graceful-shutdown timeout is configurable; by default the server waits indefinitely for shutdown to complete.
5. If the server is not responding for graceful shutdown request or to bring down the server while the server is waiting for inflight session (in standby state), use 'Force Shutdown' option.
6. If configured as a daemon, make sure the rc scripts have the stop method configured to gracefully shutdown the server in case of machine reboots and halts.
7. If Node Manager is configured, termination the Node Manager will not stop the respective servers started by them. Managed server have to be stopped separately.  

Enabling and Using JDBC Logging

Set the classpath variables in setDomainEnv.sh file under the following header

# ADD EXTENSIONS TO CLASSPATHS

On Windows

set EXT_PRE_CLASSPATH=C:\Oracle\Middleware\wlserver_10.3\server\ext\jdbc\oracle\11g\ojdbc6_g.jar 
set JAVA_OPTIONS=-Doracle.jdbc.Trace=true -Djava.util.logging.config.file=c:/temp/OracleLog.properties 

On Unix

EXT_PRE_CLASSPATH="${EXT_PRE_CLASSPATH}${CLASSPATHSEP}/reuters/oracle/product/soa/11g/fmw/wlserver_10.3/server/ext/jdbc/oracle/11g/ojdbc6_g.jar"
JAVA_OPTIONS="${JAVA_OPTIONS} -Doracle.jdbc.Trace=true -Djava.util.logging.config.file=/reuters/oracle/as01/fmw/config/admin/domains/deployplan/OracleLog.properties "

In the OracleLog.properties have the following entries ,

#### Console Handler ######

#java.util.logging.ConsoleHandler.level = ALL 
#java.util.logging.ConsoleHandler.formatter = 
#java.util.logging.SimpleFormatter 
#handlers = java.util.logging.ConsoleHandler

#### File  Handler ######

oracle.jdbc.handlers=java.util.logging.FileHandler 
java.util.logging.FileHandler.level=ALL 
java.util.logging.FileHandler.pattern=c:/temp/jdbc.log 
java.util.logging.FileHandler.count=1 
java.util.logging.FileHandler.formatter=java.util.logging.SimpleFormatter

# Uncomment and/or change the levels for more detail 
#oracle.jdbc.level = FINEST 
#oracle.jdbc.connector.level = FINE 
#oracle.jdbc.driver.level = FINEST 
#oracle.jdbc.internal.level = FINEST 
#oracle.jdbc.oci.level = FINE 
#oracle.jdbc.oracore.level = FINE 
#oracle.jdbc.pool.level = FINE 
#oracle.jdbc.rowset.level = FINEST 
#oracle.jdbc.util.level = FINEST 
#oracle.jdbc.xa.level = FINE 
#oracle.jdbc.xa.client.level = FINE 
#oracle.jpub.level = FINE 
#oracle.net.level = FINE 
#oracle.sql.level = FINEST 
#.level=CONFIG 
#oracle.level=CONFIG 
#oracle.jdbc.pool.level=CONFIG 
#oracle.jdbc.util.level=CONFIG 
#oracle.sql.level=CONFIG

#oracle.jdbc.driver.level=FINE

# This is the setting needed for sql debug 
oracle.jdbc.driver.level=FINE 
oracle.level=OFF

 If you want only the sql statements without bind variables use 
oracle.jdbc.driver.level=CONFIG

WLST Script to Monitor Weblogic Server State


import thread
import time


def conn():
    username='weblogic'
    password='welcome1'
    admurl = "t3://localhost:7001"
 
    try:
        connect(username, password, admurl)
    except ConnectionException,e:
        print 'Unable to find admin server...'
        exit()

def ServrState():
    print 'Fetching state of every WebLogic instance'
    #Fetch the state of the every WebLogic instance
    for name in serverNames:
        cd("/ServerLifeCycleRuntimes/" + name.getName())
        serverState = cmo.getState()
        if serverState == "RUNNING":
            print 'Server ' + name.getName() + ' is :' + serverState
        elif serverState == "STARTING":
            print 'Server ' + name.getName() + ' is :' + serverState
        elif serverState == "UNKNOWN":
            print 'Server ' + name.getName() + ' is :' + serverState
        else:
            print 'Server ' + name.getName() + ' is :' + serverState
        


def ApplicationsState():
    print 'Fetching state of every Application deployed on Weblogic'
    for appName in myapps:

       domainConfig()
       cd ('/AppDeployments/'+appName.getName()+'/Targets')
       mytargets = ls(returnMap='true')
       domainRuntime()
       cd('AppRuntimeStateRuntime')
       cd('AppRuntimeStateRuntime')
       for targetinst in mytargets:
    appID = appName.getApplicationIdentifier()
             navPath=getMBean('domainRuntime:/AppRuntimeStateRuntime/AppRuntimeStateRuntime')
             sts=navPath.getCurrentState(appID,targetinst)
             print "Status of " + appName.getApplicationName() + ": " + sts + ": " + targetinst
            
       print "==========================================================================="

def monitorJVMHeapSize():
    #while 1:
        for name in serverNames:
            print 'Now checking '+name.getName()
            try:
             cd("/ServerRuntimes/"+name.getName()+"/JVMRuntime/"+name.getName())
            except WLSTException,e:
             # this typically means the server is not active, just ignore
                pass
            heapSize = cmo.getHeapSizeCurrent()
            if heapSize > THRESHOLD:
             # do whatever is neccessary, send alerts, send email etc
             print 'WARNING: The HEAPSIZE is Greater than the Threshold'
            else:
                print heapSize
        #java.lang.Thread.sleep(1800000)

 
def quit():
    print 'Re-Run the script HIT any key..'
    Ans = raw_input("Are you sure Quit from WLST... (y/n)")
    if (Ans == 'y'):
        disconnect()
        stopRedirect()
        exit()
    else:
        ServrState()
 
if __name__== "main":

    #waitTime=300000
    THRESHOLD=100000000
    redirect('./logs/Server.log', 'false')        
    conn()
  
    serverNames = cmo.getServers()
    myapps = cmo.getAppDeployments()
    domainRuntime()
    ServrState()
    ApplicationsState()
    monitorJVMHeapSize()
    quit()

Let's know our JDK version differences

Much of revolution started from 1.2 onwards with JFC event delegation model as earlier version of Java i.e 1.x was much popular for Servlets and Applets than anything else.

Java Printing API was one of the area that got improved from 1.2 onwards...

Do you know that Java Uses different Floating Point Standard than compared to Microsoft. Read the article here... You must know this...

http://www.concentric.net/~ttwang/tech/javafloat.htm

http://www.cs.berkeley.edu/~wkahan/JAVAhurt.pdf
  
Differences:

WikiPedia : http://en.wikipedia.org/wiki/Java_version_history

JDK 1.0 (January 23, 1996) ·         Initial release JDK 1.1 (February 19, 1997) ·         Retooling of the AWT event model ·         Inner classes added to the language ·         JavaBeans ·         JDBC ·         RMI J2SE 1.2 (December 8, 1998) This and subsequent releases through J2SE 5.0 were rebranded retrospectively Java 2 & version name "J2SE" (Java 2 platform, Standard edition) replaced JDK to distinguish the base platform from J2EE (java 2 platform, enterprise edition) and J2ME (java 2 platform, micro edition). ·         Strictfp keyword ·         Reflection ·         Swing api integration into the core classes ·         JVM equipped with a jit compiler ·         Java plug-in ·         Java IDL ·         An IDL implementation for corba interoperability ·         Collections Framework Basic Features Security and Signed Applets docs Collections Framework docs JavaBeansTM docs Internationalization docs Networking docs Arbitrary-Precision Math docs Reflection docs Package Version Identification docs Sound docs Reference Objects docs Resources docs Object Serialization docs Extension Mechanism docs Java Archive (JAR) Files docs Java Native Interface (JNI) docs Performance Enhancements docs Miscellaneous Features              (Applet tag, Deprecation, Resources) docs Java Foundation Classes (JFC) Abstract Window Toolkit (AWT) docs Swing Components docs 2D Graphics and Imaging docs Input Method Framework docs Accessibility docs Drag-and-Drop data transfer docs Enterprise Features Interface Definition Language (IDL) docs Remote Method Invocation (RMI) docs Java Database Connectivity (JDBCTM) docs Tool Support Java Virtual Machine Debugger Interface (JVMDI) docs Java Virtual Machine Profiler Interface (JVMPI) J2SE 1.3 (may 8, 2000) ·         Hotspot jvm included ·         JavaSound ·         JNDI included in core libraries ·         Java platform debugger architecture (jpda) ·         RMI was modified to support optional compatibility with corba J2SE 1.4 (february 6, 2002) ·         assert keyword ·         Regular expressions ·         Exception chaining (allows an exception to encapsulate original lower-level exception) ·         Internet protocol version 6 (IPV6) support ·         Non-blocking nio (new input/output) ·         Logging API ·         Image i/o api for reading and writing images in formats like jpeg and png ·         Integrated XML parser and XSLT processor (JAXP) ·         Integrated security and cryptography extensions (JCE, JSSE, JAAS) ·         Java web start J2SE 5.0 (september 30, 2004) tiger [originally numbered 1.5] ·         Generics: provides compile-time (static) type safety for collections and eliminates the need for most typecasts (type conversion). ( example: typed Collections, Set(<String>)) ·         Metadata: also called annotations; allows language constructs such as classes and methods to be tagged with additional data, which can then be processed by metadata-aware utilities. ·         Autoboxing/unboxing: automatic conversions between primitive types (such as int) and primitive wrapper classes (such as integer). ·         Enumerations: the enum keyword creates a typesafe, ordered list of values (such as day.monday, day.tuesday, etc.). Previously this could only be achieved by non-typesafe constant integers or manually constructed classes (typesafe enum pattern). ·         Swing: new skinnable look and feel, called synth. ·         Var args: the last parameter of a method can now be declared using a type name followed by three dots (e.g. Void drawtext(string... Lines)). In the calling code any number of parameters of that type can be used and they are then placed in an array to be passed to the method, or alternatively the calling code can pass an array of that type. Another example: printf() function, allows variable number of different arguments. ·         Enhanced for each loop: the for loop syntax is extended with special syntax for iterating over each member of either an array or any iterable, such as the standard collection classesfix the previously broken semantics of the java memory model, which defines how threads interact through memory. ·         Automatic stub generation for rmi objects. ·         Static imports concurrency utilities in package java.util.concurrent. ·         Scanner class for parsing data from various input streams and buffers. ·         Assertions ·         StringBuilder class (in java.lang package) ·         Annotations Links: http://www2.hh.se/staff/vero/languages/05/lectures/j1.5.pdf Java SE 6 (december 11, 2006) mustang sun replaced the name "J2SE" with java se and dropped the ".0" from the version number. Beta versions were released in february and june 2006, leading up to a final release that occurred on december 11, 2006. The current revision is update 20. ·         Support for older win9x versions dropped. ·         Scripting lang support: Generic API for integration with scripting languages, & built-in mozilla javascript rhino integration ·         Dramatic performance improvements for the core platform, and swing. ·         Improved web service support through JAX-WS JDBC 4.0 support ·         Java compiler API: an API allowing a java program to select and invoke a java compiler programmatically. ·         Upgrade of JAXB to version 2.0: including integration of a stax parser. ·         Support for pluggable annotations ·         Many GUI improvements, such as integration of swingworker in the API, table sorting and filtering, and true swing double-buffering (eliminating the gray-area effect). Java se 6 update 10 A major enhancement in terms of end-user usability. ·         Java Deployment Toolkit, a set of javascript functions to ease the deployment of applets and java web start applications. ·         Java Kernel, a small installer including only the most commonly used jre classes. Enhanced updater. ·         Enhanced versioning and pack200 support: server-side support is no longer required. ·         Java quick starter, to improve cold start-up time. ·         Improved performance of java2D graphics primitives on windows, using direct3D and hardware acceleration. ·         A new Swing look and feel called NIMBUS and based on synth. ·         Next-generation java plug-in: applets now run in a separate process and support many features of web start applications. Java se 6 update 12 This release includes the highly anticipated 64-bit java plug-in (for 64-bit browsers only), windows server 2008 support, and performance improvements of java and JAVAFX applications. Features and Enhancements JDK Documentation Java Platform, Standard Edition 6 is a major feature release. The following list highlights many of the significant features and enhancements in Java SE 6 since the prior major release, J2SE 5.0. It is followed by a detailed table with links to related bugs, enhancements, and JSRs. Note, this web page relates to the Release Candidate milestone for Java SE 6. Its related Umbrella JSR 270 does not itself define specific features. Instead it enumerates features defined in other JSRs or through the concurrent maintenance review of the Java SE platform specification. The final release is expected to include all JSR 270 features, although it is possible for an approved feature to be dropped. Refer also to: Java Platform, Standard Edition Differences between 5.0 fcs and 6 Beta . Highlights of Technology Changes in Java SE 6 Choose a technology for links to further information. Collections Framework Deployment (Java Web Start and Java Plug-in) Drag and Drop Instrumentation Internationalization Support I/O Support JAR (Java Archive Files) - An annotated list of changes between the 5.0 and 6.0 releases to APIs, the jar command, and the jar/zip implementation. Java Web Start Java DB 10.2 JDBC4 Early Access The $JAVA_HOME/db subdirectory contains class libraries for Java DB, Sun Microsystems's distribution of the Apache Derby database technology. For information on Java DB, see Java DB. For information on Derby, see: Apache Derby. For documentation on this version of Java DB, see Java DB - Reference. For a description of the capabilities of this version of Java DB, see the release notes in the $JAVA_HOME/db subdirectory. This Early Access version of Java DB is built from Apache Derby 10.2.1.7 source code (revision 453926) using JDK 6 JDBC 4 APIs to build JDBC 4 driver code. Comments regarding this version of Java DB can be sent to javadb-ea@sun.com. DISCLAIMER: THIS IS EARLY ACCESS SOFTWARE AND COMES WITH NO WARRANTIES OR SUPPORT. IT IS PROVIDED "AS IS". IT IS NOT FOR PRODUCTION USE. JMX (Java Management Extensions) - A list of JMX API changes between the J2SE 5.0 and Java SE 6 releases. JPDA (Java Platform Debugger Architecture) JVM TI (Java Virtual Machine Tool Interface) http://docs.oracle.com/javase/1.5.0/docs/guide/jvmti/jvmti.html lang and util Packages Monitoring and Management for the Java Platform JConsole is Officially Supported in Java SE 6 Networking Features Performance Reflection RMI (Remote Method Invocation) Scripting Security Serialization of Objects Swing VM (Java Virtual Machine) Detailed Table of Technology Changes in Java SE 6 Items are ordered by area/component. The first column indicates the scope of a change: jsr – A larger feature or feature set having its own Java Specification Request api – A smaller feature that adds new Java APIs (application programming interfaces) imp – An implementation enhancement that does not involve new APIs, for example, a performance improvement SCOPE AREA / COMPONENT SYNOPSIS RFE api client/2d ImageIO: GIF writer 4339415 imp client/2d Native Text Rendering Parity 4726365 imp client/2d Improved hardware acceleration on Windows 5104393 imp client/2d Single-threaded rendering for OpenGL pipelines 6219284 api client/awt Pop-up splash screen at beginning of Java startup 4247839 api client/awt Java applications can access desktop applications 6255196 api client/awt Improved modal dialogs 4080029 imp client/awt XAWT is the default Toolkit on Solaris 5049146 api client/awt Windows system-tray support 4310333 imp client/awt Better support for input in non-English locales 4360364 imp client/awt Live resizing 6199167 imp client/deploy Improved application deployment across browsers 6329487 api client/deploy Allow JAR files to be shared across installed JREs 6271065 imp client/deploy Improved user experience in JRE/JDK installer 5079209 imp client/deploy Improved security 6222485 imp client/deploy Direct execution of JAR files on Linux 6211008 imp client/deploy Improved desktop integration in Java Web Start 4625362 imp client/deploy Improved IFTW installer 6198632 imp client/deploy Improved startup & footprint for plugin/webstart 6329480 imp client/deploy Mozilla Firefox browser support 6216340 imp client/deploy Default Java on Linux 6211006 imp client/deploy Improved user experience in Java Plug-in and Java Web Start 6205064 imp client/deploy Unified download engine 4802551 imp client/deploy Support Mozilla and Firefox family browsers. 6216340 api client/dnd A way to avoid hangs on retrieval of clipboard data 4818143 imp client/i18n Support for important locales 4324505 imp client/i18n Japanese calendar 4609228 api client/i18n Resource bundle enhancements 5102289 api client/i18n Normalizer API 4221795 api client/i18n Pluggable locales: Pluggability for break iterators 4052440 api client/i18n Pluggable locales: Pluggability for locale names, formatters, and collators 4052440 imp client/l10n Chinese localization for JDK tools 6209342 imp client/swing GTK Native L&F Fidelity 6185456 imp client/swing Through-the-stack: Reduced footprint / startup time 6329480 imp client/swing Native look & feel fidelity  imp client/swing Avalon Look-and-Feel 6329475 api client/swing JTable sorting, filtering, and highlighting 4747079 api client/swing JTabbedPane: Tabs as Components 4499556 imp client/swing Windows native L&F fidelity 5106661 api client/swing SwingWorker 4681682 api client/swing Improve Drag & Drop features for Swing Components 4468566 api client/swing Extend SpringLayout 4726194 api client/swing Text Document Printing 4791649 imp client/swing Improved Painting Performance (fix grey boxes) 4967886 jsr core/core JSR 223: Scripting for the Java Platform 6249843 api core/debug Multiple Simultaneous Agents 4772582 api core/debug Added Heap Capabilities to JPDA 4914266 api core/debug Attach-on-demand 6173612 api core/debug JVMPI and JVMDI have been removed. 4914266 api core/jndi Read-timeout specification for LDAP operations 6176036 api core/libs Array Reallocation API 4655503 imp core/libs BigDecimal optimizations for specjbb++ api core/libs Floating point: Add IEEE 754 recommended functions to java.lang.{{,Strict}Math} 4406429 api core/libs Standard service-provider API (java.util.Service) 4640520 api core/libs Collections and Concurrency Updates 6268386 api core/libs IO Enhancement: Password Prompting 4050435 api core/libs IO Enhancement: File Attributes 6216563 api core/libs IO Enhancement: Method for Discovering Free Disk Space 4057701 imp core/libs IO Enhancement: Long pathnames on Windows 4403166 api core/libs Low-level Java compiler API for IDEs 4813736 jsr core/libs JSR 202: Java Class File Specification Update 4639391 jsr core/libs JSR 199: Java compiler API 4164450 imp core/libs Improved perceived footprint 6280693 api core/libs Deques 6192552 api core/libs Navigable Maps and Sets 4155650 imp core/libs BitSet Updates 4963875, 4979017, 4979028,4979031, 5030267, 6222207,6404711 imp core/libs Performance Improvements when compiling using network file systems 4770745 imp core/m&m Improved diagnosability of OutOfMemoryError 6173515 api core/m&m Generic annotations for MBean descriptor contents 6221321 api core/m&m Support for java.util.concurrent locks in the lock related facility 5086470 imp core/m&m jconsole is more user-friendly 6174397 api core/m&m Small-scale improvements to JMX Monitor API 6222961 api core/m&m descriptors added to all types of MBean 6204469 api core/m&m MXBeans added to JMX 6175517 api core/net Light-weight HTTP server 6270015 api core/net Internationalized resource identifiers 5085902 api core/net Default CookieManager implementation 6244040 imp core/net SPNEGO HTTP authentication 6260531 api core/net International domain names 4737170 api core/net Programmatic access to network parameters 4691932 imp core/sec Native platform GSS integration 6202035, 6345202 imp core/sec SPNEGO in Java GSS 6239635 imp core/sec MS CAPI Keystore provider 6318171 imp core/sec Better support for NSS keystore 6273877 imp core/sec Improved Policy performance 5037004 imp core/sec JSR 268: Java Smart Card I/O API 6239117 jsr core/sec JSR 105: XML DSig 4635230 api core/sec Enhance certificate APIs 4635060 jsr core/tools JSR 269: Standard pluggabilty API for annotation processors (APT) 6222574 imp core/tools javac: Support for split verification 6227862, 6227862, 5110170,5110184, 6217263 imp core/tools javac: Implement JSR 175'sjava.lang.SuppressWarnings 4986256 imp core/tools Class-path wildcards 6268383 jsr ee/ee JSR 250: Common annotations 6304697 imp ee/jdbc Extended JDBC-ODBC bridge to enable JDBC 4.0 EoD features 6290312 jsr ee/jdbc JSR 221: JDBC 4.0 6290312 imp ee/xml JAXP 1.4 JSR 206: Java API for XML Processing 6317994 jsr ee/xml Support for the Web Services stack JSR 222: JAXB 2.0 JSR 224: JAX-RPC 2.0 JSR 173: STAX JSR 181: Web Services Metadata 6245626 api ee/xml JavaBeans Activation Framework (JAF) 6254474 imp vm/compilers Improved performance of compiled code 5079711, 6206844, 6239807,4850474, 5003419, 5004907, 5101346,6190413, 6191063, 6196383, 6196722, 6211497,6232485, 6233627, 6245809, 6251002, 6262235, imp vm/c1 Linear scan register allocator for C1 6320351 imp vm/c2 Improved loop optimization 5073662, 5074608, 5091921,6260293 imp vm/c2 Escape analysis 6339956 imp vm/c2 Lock coarsening 6245809 imp vm/gc CMS: Parallelize concurrent marking imp vm/gc Parallel compaction imp vm/runtime Improve uncontended synchronization performance imp vm/runtime Improved performance of contended synchronization operations imp vm/runtime Faster format checker/class-file parser imp vm/runtime Improved startup time 6179212 imp vm/runtime Improved runtime performance imp vm/runtime Improved JNI performance 5086424 imp vm/runtime Class circularity detection 4699981 imp vm/runtime DTrace support in the VM On Printing Thats something not out of box in Java Refer to this: http://code.google.com/p/ups-php/  http://code.google.com/p/zxing/  http://www.google.com/chrome/intl/en/p/cloudprint.html http://code.google.com/p/escprinter/ http://code.google.com/p/jzebra/

Java SE 7 Features and Enhancements

Java Platform, Standard Edition 7 is a major feature release. This document includes information on features and enhancements in Java SE 7 and in JDK 7, Oracle's implementation of Java SE 7. 

Contents

• Highlights of Technology Changes in Java SE 7
• Important RFEs Addressed in Java SE 7
• Important RFEs Addressed in JDK 7
• Known Issues

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Highlights of Technology Changes in Java SE 7

The following list contains links to the the enhancements pages in the Java SE 7 guides documentation. Choose a technology for further information.

• Swing
• IO and New IO
• Networking
• Security
• Concurrency Utilities
• Rich Internet Applications (RIA)/Deployment
  • Requesting and Customizing Applet Decoration in Dragg able Applets
  • Embedding JNLP File in Applet Tag
  • Deploying without Codebase
  • Handling Applet Initialization Status with Event Handlers
• Java 2D
• Java XML - JAXP, JAXB, and JAX-WS
• Internationalization
• java.lang Package
  • Multithreaded Custom Class Loaders in Java SE 7
• Java Programming Language
  • Binary Literals
  • Strings in switch Statements
  • The try-with-resources Statement
  • Catching Multiple Exception Types and Rethrowing Exceptions with Improved Type Checking
  • Underscores in Numeric Literals
  • Type Inference for Generic Instance Creation
  • Improved Compiler Warnings and Errors When Using Non-Reifiable Formal Parameters with Varargs Methods
• Java Virtual Machine (JVM)
  • Java Virtual Machine Support for Non-Java Languages
  • Garbage-First Collector
  • Java HotSpot Virtual Machine Performance Enhancements
• JDBC

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