First time compiling java codes

Sirs,
I am able to compile my codes but when I try to execute them
the message below is shown....
java.lang.NoSuchMethodError
How do I fix it ? Thank you all

The complete error was
java.lang.NoSuchMethodError: main
Exception in thread "main" Exit code: 1
There were errors
Then the class you are trying to run:
java [-cp [i]classpath] ThisClass
(let's assume it is named ThisClass)
does not have the required:
public static void main(String[] args)
method implemented, as already pointed out earlier.

Similar Messages

Error while running compiled java code

Hi
I have an evaluation license of the JDeveloper2.0 installed on my WindowsNT 4.0 workstation.
I seem to have a problem running my compiled jave code. After compiling the source code(.java file) when I try to run the same I get a message saying
"<FileName> not found in outpath classpath or sourcepath ".
What does this mean and how can I rectify it?
Regards
Sree
null

Your classpath tells Java run time where to look for the class files it needs. In JDeveloper the class path is set in your project properties. Select Project->Properties and check that the source and output paths correspond to your myprojects and myclasses directories.

EXCEPTION_ACCESS_VIOLATION (0xc0000005) on compiled Java code

I'm confronted with the following error of this code.
http://db-www.naist.jp/~makoto-y/tmp/Int2LongHash.java
The exception appears only when the system gets high-load.
Is there work-arounds?
I've tried also with jdk1.5.0_06, but the same error occurred.
Converting the inner class to a top-level class has no effects.
# An unexpected error has been detected by Java Runtime Environment:
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x00a2cd75, pid=1540, tid=2968
# Java VM: Java HotSpot(TM) Client VM (1.6.0-beta2-b86 mixed mode)
# Problematic frame:
# J org.metabrick.xbird.util.collections.Int2LongHash$Int2LongLRUMap$ChainedEntry.recordRemoval(Lorg/metabrick/xbird/util/collections/Int2LongHash;)V
# If you would like to submit a bug report, please visit:
# http://java.sun.com/webapps/bugreport/crash.jsp
--------------- T H R E A D ---------------
Current thread (0x003f6800): JavaThread "main" [_thread_in_Java, id=2968]
siginfo: ExceptionCode=0xc0000005, writing address 0xfc2cee54
Registers:
EAX=0x42d43500, EBX=0x03d3ee00, ECX=0x03d3ee00, EDX=0x07911838
ESP=0x0091f760, EBP=0x0091f778, ESI=0x0790f9f8, EDI=0xfc2cee38
EIP=0x00a2cd75, EFLAGS=0x00010203
Top of Stack: (sp=0x0091f760)
0x0091f760: 0790ac30 079220b0 00000200 03d917f8
0x0091f770: 00000000 6d955aa7 0091f7a8 00a2c9dc
0x0091f780: 00000200 00000000 0091f7e8 00a12d50
0x0091f790: 5ab674cf 00000000 07911838 03d3ee00
0x0091f7a0: 03d8b700 00000010 0091f7f8 00a2c000
0x0091f7b0: 03d8b700 078e4af4 00000010 00a2ab04
0x0091f7c0: 078e4af4 03d8b700 00000010 00000001
0x0091f7d0: 00000000 6d955ae7 5ab674d0 00000000
Instructions: (pc=0x00a2cd75)
0x00a2cd65: 20 8b fe c1 ef 09 c6 87 80 b1 5b 48 00 8b 79 20
0x00a2cd75: 89 77 1c c1 ef 09 c6 87 80 b1 5b 48 00 8b e5 5d
Stack: [0x008d0000,0x00920000), sp=0x0091f760, free space=317k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
J org.metabrick.xbird.util.collections.Int2LongHash$Int2LongLRUMap$ChainedEntry.recordRemoval(Lorg/metabrick/xbird/util/collections/Int2LongHash;)V
J org.metabrick.xbird.util.collections.Int2LongHash.remove(I)J
J org.metabrick.xbird.util.collections.Int2LongHash$Int2LongLRUMap.addEntry(IIJLorg/metabrick/xbird/util/collections/Int2LongHash$BucketEntry;)V
J org.metabrick.xbird.util.collections.Int2LongHash.put(IJ)J
J org.metabrick.xbird.xquery.util.StringChunk.storeCharChunk([CII)J
J org.metabrick.xbird.xquery.util.StringChunk.store([CII)J
J org.metabrick.xbird.xquery.dm.dtm.BigDocumentTable.setTextAt(J[CII)J
J org.metabrick.xbird.xquery.dm.dtm.DocumentTableBuilder.createTextNode()V
J org.metabrick.xbird.xquery.dm.dtm.DocumentTableBuilder.endElement(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)V
J org.apache.xerces.parsers.AbstractSAXParser.endElement(Lorg/apache/xerces/xni/QName;Lorg/apache/xerces/xni/Augmentations;)V
J org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanEndElement()I
J org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Z)Z
j org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Z)Z+24
j org.apache.xerces.parsers.XML11Configuration.parse(Z)Z+132
j org.apache.xerces.parsers.XML11Configuration.parse(Lorg/apache/xerces/xni/parser/XMLInputSource;)V+29
j org.apache.xerces.parsers.XMLParser.parse(Lorg/apache/xerces/xni/parser/XMLInputSource;)V+9
j org.apache.xerces.parsers.AbstractSAXParser.parse(Lorg/xml/sax/InputSource;)V+43
j org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(Lorg/xml/sax/InputSource;)V+43
j org.metabrick.xbird.xquery.dm.instance.DocumentTableModel.loadDocument(Ljava/io/InputStream;)V+35
j org.metabrick.xbird.client.tools.command.ImportDocument.process([Ljava/lang/String;)Z+99
j org.metabrick.xbird.client.tools.CommandInvoker.executeCommand([Ljava/lang/String;)Z+8
j org.metabrick.xbird.client.tools.CommandInvoker.run([Ljava/lang/String;)V+66
j org.metabrick.xbird.client.tools.CommandInvoker.main([Ljava/lang/String;)V+19
v ~StubRoutines::call_stub
--------------- P R O C E S S ---------------
Java Threads: ( => current thread )
0x48aa5000 JavaThread "Low Memory Detector" daemon [_thread_blocked, id=3636]
0x48aa0800 JavaThread "CompilerThread0" daemon [_thread_blocked, id=4076]
0x48a9e400 JavaThread "Attach Listener" daemon [_thread_blocked, id=3144]
0x48aac400 JavaThread "Signal Dispatcher" daemon [_thread_blocked, id=2248]
0x48a86c00 JavaThread "Finalizer" daemon [_thread_blocked, id=2664]
0x48a82800 JavaThread "Reference Handler" daemon [_thread_blocked, id=2700]
=>0x003f6800 JavaThread "main" [_thread_in_Java, id=2968]
Other Threads:
0x48a7f400 VMThread [id=4028]
0x48aa6800 WatcherThread [id=3704]
VM state:not at safepoint (normal execution)
VM Mutex/Monitor currently owned by a thread: None
Heap
def new generation total 72576K, used 28616K [0x029d0000, 0x07890000, 0x07890000)
eden space 64512K, 32% used [0x029d0000, 0x03e6fdd0, 0x068d0000)
from space 8064K, 92% used [0x068d0000, 0x07022230, 0x070b0000)
to space 8064K, 0% used [0x070b0000, 0x070b0000, 0x07890000)
tenured generation total 967936K, used 253073K [0x07890000, 0x429d0000, 0x429d0000)
the space 967936K, 26% used [0x07890000, 0x16fb4788, 0x16fb4800, 0x429d0000)
compacting perm gen total 12288K, used 5879K [0x429d0000, 0x435d0000, 0x469d0000)
the space 12288K, 47% used [0x429d0000, 0x42f8dd08, 0x42f8de00, 0x435d0000)
No shared spaces configured.
Dynamic libraries:
0x00400000 - 0x00423000      C:\Program Files\Java\jdk1.6.0\bin\javaw.exe
0x7c940000 - 0x7c9dd000      C:\WINDOWS\system32\ntdll.dll
0x7c800000 - 0x7c931000      C:\WINDOWS\system32\kernel32.dll
0x77d80000 - 0x77e29000      C:\WINDOWS\system32\ADVAPI32.dll
0x77e30000 - 0x77ec1000      C:\WINDOWS\system32\RPCRT4.dll
0x77cf0000 - 0x77d7f000      C:\WINDOWS\system32\USER32.dll
0x77ed0000 - 0x77f17000      C:\WINDOWS\system32\GDI32.dll
0x762e0000 - 0x762fd000      C:\WINDOWS\system32\IMM32.DLL
0x60740000 - 0x60749000      C:\WINDOWS\system32\LPK.DLL
0x73f80000 - 0x73feb000      C:\WINDOWS\system32\USP10.dll
0x77bc0000 - 0x77c18000      C:\WINDOWS\system32\msvcrt.dll
0x7c340000 - 0x7c396000      C:\Program Files\Java\jdk1.6.0\jre\bin\msvcr71.dll
0x6d7f0000 - 0x6da2f000      C:\Program Files\Java\jdk1.6.0\jre\bin\client\jvm.dll
0x76af0000 - 0x76b1b000      C:\WINDOWS\system32\WINMM.dll
0x6d310000 - 0x6d318000      C:\Program Files\Java\jdk1.6.0\jre\bin\hpi.dll
0x76ba0000 - 0x76bab000      C:\WINDOWS\system32\PSAPI.DLL
0x6d7a0000 - 0x6d7ac000      C:\Program Files\Java\jdk1.6.0\jre\bin\verify.dll
0x6d3a0000 - 0x6d3bf000      C:\Program Files\Java\jdk1.6.0\jre\bin\java.dll
0x6d7e0000 - 0x6d7ef000      C:\Program Files\Java\jdk1.6.0\jre\bin\zip.dll
0x6d560000 - 0x6d573000      C:\Program Files\Java\jdk1.6.0\jre\bin\net.dll
0x719e0000 - 0x719f7000      C:\WINDOWS\system32\WS2_32.dll
0x719d0000 - 0x719d8000      C:\WINDOWS\system32\WS2HELP.dll
0x6d580000 - 0x6d589000      C:\Program Files\Java\jdk1.6.0\jre\bin\nio.dll
VM Arguments:
jvm_args: -Xmx1024m -Xms1024m
java_command: org.metabrick.xbird.client.tools.CommandInvoker -col /xmark import document C:\Software\xmark\xmark100.xml
Launcher Type: SUN_STANDARD
Environment Variables:
JAVA_HOME=C:\Program Files\Java\jdk1.6.0
PATH=C:\Program Files\Java\jdk1.6.0\bin;D:\Software\maven-1.0.2\bin;D:\cygwin\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;D:\Software\apache-ant-1.6.5\bin;C:\ghc\ghc-6.4.2\bin;C:\Program Files\QuickTime\QTSystem\
USERNAME=yui
OS=Windows_NT
PROCESSOR_IDENTIFIER=x86 Family 15 Model 4 Stepping 4, GenuineIntel
--------------- S Y S T E M ---------------
OS: Windows XP Build 2600 Service Pack 2
CPU:total 2 family 15, cmov, cx8, fxsr, mmx, sse, sse2, ht
Memory: 4k page, physical 2096404k(108924k free), swap 3511144k(1471688k free)
vm_info: Java HotSpot(TM) Client VM (1.6.0-beta2-b86) for windows-x86, built on Jun 2 2006 00:36:31 by "java_re" with unknown MS VC++:1310

The following is the error that I got with using JDK 1.5.
# An unexpected error has been detected by HotSpot Virtual Machine:
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x00b8c9f8, pid=4024, tid=1608
# Java VM: Java HotSpot(TM) Client VM (1.5.0_06-b05 mixed mode)
# Problematic frame:
# J org.metabrick.xbird.util.collections.Int2LongHash$Int2LongLRUMap$ChainedEntry.recordRemoval(Lorg/metabrick/xbird/util/collections/Int2LongHash;)V
--------------- T H R E A D ---------------
Current thread (0x00036190): JavaThread "main" [_thread_in_Java, id=1608]
siginfo: ExceptionCode=0xc0000005, writing address 0xfa424094
Registers:
EAX=0x00040e40, EBX=0xfa424078, ECX=0x05bd3fc0, EDX=0x05bd3fc0
ESP=0x0007f578, EBP=0x0007f590, ESI=0xfa424078, EDI=0x081c8168
EIP=0x00b8c9f8, EFLAGS=0x00010203
Top of Stack: (sp=0x0007f578)
0x0007f578: 081c1fa8 6d7d1061 022dd1c8 00000000
0x0007f588: 00000200 00000200 0007f5c8 00b8c598
0x0007f598: 0899f428 05bd3fc0 00000200 00000000
0x0007f5a8: 0007f5c8 00b41018 00000200 000001cb
0x0007f5b8: 05c50338 05c19448 05bd3fc0 000001a8
0x0007f5c8: 0007f648 00b8b880 07dd565c 0899f428
0x0007f5d8: 022dd1cb 00000000 08976190 00b8054c
0x0007f5e8: 00001000 0000af89 00001000 6d7d1061
Instructions: (pc=0x00b8c9f8)
0x00b8c9e8: 89 5f 20 c1 e8 09 c6 80 00 a9 6c 48 00 8b 72 20
0x00b8c9f8: 89 7e 1c c1 ee 09 c6 86 00 a9 6c 48 00 8b e5 5d
Stack: [0x00040000,0x00080000), sp=0x0007f578, free space=253k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
J org.metabrick.xbird.util.collections.Int2LongHash$Int2LongLRUMap$ChainedEntry.recordRemoval(Lorg/metabrick/xbird/util/collections/Int2LongHash;)V
J org.metabrick.xbird.util.collections.Int2LongHash.remove(I)J
J org.metabrick.xbird.util.collections.Int2LongHash$Int2LongLRUMap.addEntry(IIJLorg/metabrick/xbird/util/collections/Int2LongHash$BucketEntry;)V
J org.metabrick.xbird.util.collections.Int2LongHash.put(IJ)J
J org.metabrick.xbird.xquery.util.StringChunk.storeCharChunk([CII)J
J org.metabrick.xbird.xquery.util.StringChunk.store([CII)J
J org.metabrick.xbird.xquery.dm.dtm.BigDocumentTable.setTextAt(J[CII)J
J org.metabrick.xbird.xquery.dm.dtm.DocumentTableBuilder.createTextNode()V
J org.metabrick.xbird.xquery.dm.dtm.DocumentTableBuilder.endElement(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)V
J com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.endElement(Lcom/sun/org/apache/xerces/internal/xni/QName;Lcom/sun/org/apache/xerces/internal/xni/Augmentations;)V
J com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanEndElement()I
J com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Z)Z
v ~OSRAdapter
j com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Z)Z+24
j com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Z)Z+118
j com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Lcom/sun/org/apache/xerces/internal/xni/parser/XMLInputSource;)V+29
j com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Lcom/sun/org/apache/xerces/internal/xni/parser/XMLInputSource;)V+9
j com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Lorg/xml/sax/InputSource;)V+43
j org.metabrick.xbird.xquery.dm.instance.DocumentTableModel.loadDocument(Ljava/io/InputStream;)V+35
j org.metabrick.xbird.client.tools.command.ImportDocument.process([Ljava/lang/String;)Z+102
j org.metabrick.xbird.client.tools.CommandInvoker.executeCommand([Ljava/lang/String;)Z+8
j org.metabrick.xbird.client.tools.CommandInvoker.run([Ljava/lang/String;)V+66
j org.metabrick.xbird.client.tools.CommandInvoker.main([Ljava/lang/String;)V+19
v ~StubRoutines::call_stub
V [jvm.dll+0x845a9]
V [jvm.dll+0xd9317]
V [jvm.dll+0x8447a]
V [jvm.dll+0x8b44a]
C [java.exe+0x14c5]
C [java.exe+0x64dd]
C [kernel32.dll+0x16fd7]
--------------- P R O C E S S ---------------
Java Threads: ( => current thread )
0x00aa7490 JavaThread "Low Memory Detector" daemon [_thread_blocked, id=1780]
0x00aa60f0 JavaThread "CompilerThread0" daemon [_thread_blocked, id=3456]
0x00aa53f8 JavaThread "Signal Dispatcher" daemon [_thread_blocked, id=2544]
0x00a96c80 JavaThread "Finalizer" daemon [_thread_blocked, id=856]
0x00a957e8 JavaThread "Reference Handler" daemon [_thread_blocked, id=816]
=>0x00036190 JavaThread "main" [_thread_in_Java, id=1608]
Other Threads:
0x0003fbd0 VMThread [id=3592]
0x00ab0e20 WatcherThread [id=3108]
VM state:not at safepoint (normal execution)
VM Mutex/Monitor currently owned by a thread: None
Heap
def new generation total 72576K, used 59965K [0x02ae0000, 0x079a0000, 0x079a0000)
eden space 64512K, 80% used [0x02ae0000, 0x05d8f7b0, 0x069e0000)
from space 8064K, 99% used [0x069e0000, 0x071bfff8, 0x071c0000)
to space 8064K, 0% used [0x071c0000, 0x071c0000, 0x079a0000)
tenured generation total 967936K, used 451270K [0x079a0000, 0x42ae0000, 0x42ae0000)
the space 967936K, 46% used [0x079a0000, 0x23251ab0, 0x23251c00, 0x42ae0000)
compacting perm gen total 8192K, used 5367K [0x42ae0000, 0x432e0000, 0x46ae0000)
the space 8192K, 65% used [0x42ae0000, 0x4301dfb0, 0x4301e000, 0x432e0000)
No shared spaces configured.
Dynamic libraries:
0x00400000 - 0x0040c000      C:\Program Files\Java\jdk1.5.0_06\bin\java.exe
0x7c940000 - 0x7c9dd000      C:\WINDOWS\system32\ntdll.dll
0x7c800000 - 0x7c931000      C:\WINDOWS\system32\kernel32.dll
0x77d80000 - 0x77e29000      C:\WINDOWS\system32\ADVAPI32.dll
0x77e30000 - 0x77ec1000      C:\WINDOWS\system32\RPCRT4.dll
0x77bc0000 - 0x77c18000      C:\WINDOWS\system32\MSVCRT.dll
0x6d6e0000 - 0x6d874000      C:\Program Files\Java\jdk1.5.0_06\jre\bin\client\jvm.dll
0x77cf0000 - 0x77d7f000      C:\WINDOWS\system32\USER32.dll
0x77ed0000 - 0x77f17000      C:\WINDOWS\system32\GDI32.dll
0x76af0000 - 0x76b1b000      C:\WINDOWS\system32\WINMM.dll
0x762e0000 - 0x762fd000      C:\WINDOWS\system32\IMM32.DLL
0x60740000 - 0x60749000      C:\WINDOWS\system32\LPK.DLL
0x73f80000 - 0x73feb000      C:\WINDOWS\system32\USP10.dll
0x6d2f0000 - 0x6d2f8000      C:\Program Files\Java\jdk1.5.0_06\jre\bin\hpi.dll
0x76ba0000 - 0x76bab000      C:\WINDOWS\system32\PSAPI.DLL
0x6d6b0000 - 0x6d6bc000      C:\Program Files\Java\jdk1.5.0_06\jre\bin\verify.dll
0x6d370000 - 0x6d38d000      C:\Program Files\Java\jdk1.5.0_06\jre\bin\java.dll
0x6d6d0000 - 0x6d6df000      C:\Program Files\Java\jdk1.5.0_06\jre\bin\zip.dll
0x6d530000 - 0x6d543000      C:\Program Files\Java\jdk1.5.0_06\jre\bin\net.dll
0x719e0000 - 0x719f7000      C:\WINDOWS\system32\WS2_32.dll
0x719d0000 - 0x719d8000      C:\WINDOWS\system32\WS2HELP.dll
0x6d550000 - 0x6d559000      C:\Program Files\Java\jdk1.5.0_06\jre\bin\nio.dll
VM Arguments:
jvm_args: -Xmx1024m -Xms1024m -ea
java_command: org.metabrick.xbird.client.tools.CommandInvoker -col /xmark import document C:\Software\xmark\xmark100.xml
Launcher Type: SUN_STANDARD
Environment Variables:
JAVA_HOME=C:\Program Files\Java\jdk1.6.0
PATH=C:\Program Files\Java\jdk1.6.0\bin;D:\Software\maven-1.0.2\bin;D:\cygwin\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;D:\Software\apache-ant-1.6.5\bin;C:\ghc\ghc-6.4.2\bin;C:\Program Files\QuickTime\QTSystem\
USERNAME=yui
OS=Windows_NT
PROCESSOR_IDENTIFIER=x86 Family 15 Model 4 Stepping 4, GenuineIntel
--------------- S Y S T E M ---------------
OS: Windows XP Build 2600 Service Pack 2
CPU:total 2 family 15, cmov, cx8, fxsr, mmx, sse, sse2, ht
Memory: 4k page, physical 2096404k(370660k free), swap 3511144k(1545452k free)
vm_info: Java HotSpot(TM) Client VM (1.5.0_06-b05) for windows-x86, built on Nov 10 2005 11:12:14 by "java_re" with MS VC++ 6.0

How to check for a logic bomb in compiled java code ?

I have couple of security requirements.
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2. Is there any way to monitor memory utilized by class when running inside a constructor ?

1. Let me see if you can define 'logic bomb', then maybe a answer can be supplied. If you simply mean malicious code, then in general you cannot. You can attempt to do the kinds of things that antivirus software does, like check for the existence of known malicious code and code patterns, but that won't work any better on Java than it does on anything else.
2. Google java profiling. Also, for something relatively simple, read about jconsole.

Not Able to Compile Java code

Hi Java Gurus
I am not able to compile this code Pl help
class For {
public static void main (String [] args) {
int I = 0;
show:
     if (I < 2) {
System.out.print("I is " + I);
I++;
continue show;
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class For {
public static void main (String [] args) {
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Help required in compiling Java Code.

I have java1.6 installed on my PC but I want to compile my code in such a way that
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calypso wrote:
Im not 100% sure of this but I would of thought a program will compile on any version of java as long as you dont use classes that are exclusive to higher version of java
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Obviously it's not the copmiler's fault. You need to fix your code.
Here is a link to the Java Language Specification.
The link is to section 3.8 - Identifiers.
It describes the acceptable naming:
http://java.sun.com/docs/books/jls/second_edition/html/lexical.doc.html#40625
Perhaps your editor is not saving the text file in an appropriate format.
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Try vim http://www.vim.org
or SciTE http://www.scintilla.org/SciTE.html

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I found a class: com.sun.tools.apt.main.JavaCompiler
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application work?Probably most reliably using Runtime.exec().
I found a class:
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Hi,
I have class (say A) which has an inner class (say B). There is a method(say m1) in A which has a return type as a Vector (say v1). The skeletal of the code is as :-
public class A {
public A (String mesg) {
System.out.println(mesg);
//inner class B starts
public class B {
public String name;
public int age;
public B (String name, int age) {
this.name = name;
this.age = age;
//inner class B ends
public final Vector m1 (String code) {
Vector v1 = new Vector();
B b;
if (code.equals("1111")) {
b = new B("Tutty",26);
v1.addElement(b);
return v1;
public final String m2 (B b1) {
return b1.name;
public final int m3 (B b1) {
return b1.age;
// end of class A
The above class is called in the following code :-
public class check{
public static void main(String args[]) {
A a1 = new A1("Hello");
Vector v = new Vector();
v = a1.m1("1111");
for (int i=0; i<=v.size(); i++) {
String name = a1.m2(v.elementAt(i));
//end of class check
When i compile the above class check.java , i get the following error:-
check.java:15: m2(A.B) in A cannot be applied to (java.lang.Object)
String name = a1.m2(v.elementAt(i));
^
1 error
Kindly help me in rectifying the error.
Thanks in advance.
regards,
Parag, Asmita.

Hi,
Thanks for the re-designed code.
But i think if i tell you what exactly we are aiming at, may be you can give us some better and a compact solution.
We are writing some classes which are based upon entities like student, department etc etc. The return type of the various methods in these classes was becoming a debatable issue, esp. when the output was in the form of an m by n matrix...basically of 'm' columns ('m' fields of the table which was queried) and 'n' rows(records). Out of the various options, we decided that we pass every single record (of the result set) as an object (which will be non-interpretable by the programmer using our class) in a single vector.
Speaking in an elaborate way, if the query fired was like "show departments with code and name", the output was :-
"select deptcode,deptname from dept order by deptcode";
deptcode deptname
01 Chemical Enginnering
02 Computer Engineering
(etc etc)
Now we decided to pass the above as :-
Vector v1 = new Vector();
and to ' v1' we didn't want to add the string as it is but the object of the record like
v1.addElement ( objectOf(01 and Chemical Engineering) );
v1.addElement ( objectOf(02 and Computer Engineering) );
Now this 'objectOf' was upto us to decide.
So we decided that it can be an object of some inner class (in our case B). But now we realised that we have to reveal the class B also to others (during the A.B casting). So is there a way we can keep this 'objectOf' just to ourselves and when the programmer asks for 'getDeptCode(objectOf(01 and Chemical Engineering))', we have our method to interpret the argument passed and then pass the department code.
I hope i have not bugged much and made myself clear. I am sure the doubt may be silly, but we have still not come down to any solution and hence we seek help/suggestions.
thanks,
Asmita.

How to get server date and time using java code

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I'm new to java. I have one doubt about getting date and time of the server. can anyone give some sample code to get that.
thanks in regards
Gopi.

you need 2 things
1. something on the application server which exposes the servers time/date
2. something on the client which makes use of your time service
for instance, you could write a ServerTimeServlet that clients can call to get the time according to the server. or, if you've got a database in the server, often database software will provide a Time procedure or similar that does this, so you can use a simple SQL query to get the latest time

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I still dont know what is wrong, it works just fine in JCreator but, when I try to use the command prompt it still gives me the same error message. Also I have made sure that the code is in the same directory with the command.

Thanks for the advice Kitty, that was the command I
was using javac <FileName.java>. I did, however,
update my classpath and the path variables like you
mentioned, but I am still recieving the same error
message. I just cannot figure out where the error in
the code is. =(Okay... apparently you need a little help...
So to help you clarify thing a bit...
Let's start here...
This error below...
C:\myfolder\test>javac VariableDemo.java
'javac' is not recognized as an internal or external command,
operable program or batch file.... is what you get if the OS does not know the path to javac.exe...
if you type path at the command prompt you will see what your "System" path is, which would include an entry that would point to you sdk, something like "C:\YourJavaSDKFolder\bin";C:\someotherprogramfolder;
This path has nothing to do with the classpath. Your system uses this path to find executables to run you programs ( although many are locations are actually in your registry an therefore no path entry is needed... i.e. MS Word )...
This error...
C:\myfolder\test>javac VariableDemo.java
error: cannot read: VariableDemo.java
1 errormeans that your compiler was not able to locate your *.java file. I was able to replicate because VariableDemo.java does not exist on my machine, so javac.exe naturally could not find the *.java file...
javac.exe does not check the "System" path to find class files, so even though you saved you file in your "bin" folder of the SDK, javac would not know it there...
the way that javac.exe is able to find you class files is either by the default "." as stated before which is your current working directory
( noted by your command prompt ... C:\myfolder\test> )
or if you had specified your classpath either as an argument...
C:\>javac -classpath c:\myfolder\test VariableDemo.javaor by setting the "classpath" environment variable either temporarily in you command prompt by typing
set classpath=c:\myfolder\testor setting as you "System" environment variable by ( assuming Win XP though it similar for NT and 2000 ) via System Properties|Advance Tab|Environment Variable... Read your OS documentation for details involving setting your Environment Variable...
as for why JCreator or what ever IDE you are using is able to do it, is because, part of what it does is temporarily pass the classpath information to the compiler automatically... so that you won't need to do it... and which is why IDE are generally not recommended to beginners to learn Java... It does to much stuff you... hence you classpath issue...
anyway, check out the links provided for you for further and more detail information on setting the "classpath" on other Java basic...
- MaxxDmg...
- ' He who never sleeps... '

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* The following was the ouput for my coding,
O/P:-
This run took 0 Hours ;1.31 Minutes ;78.36 Seconds
*** In the above output , the output should come exactly what hours , minutes and seconds for my process,
but in my code the minutes are converted into seconds(It should not)...
* Here is my coding,
    static long start_time;
    public static void startTime()
        start_time = System.currentTimeMillis();
    public static void endTime()
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        long end_time = System.currentTimeMillis();
        float t = end_time - start_time;
        float sec = t / 1000;
        float min = 0, hr = 0;
        if (sec > 60) {
            min = sec / 60;
        if (min > 60) {
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* Hi flounder, Is following code will wotk perfectly?
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Hello... i have an ide applicaton for writing / developing java programs.
but i have a little question to ask.. i want when i click on a button "compile" in my application it should compile the partricular java file in the jdk dir rrorn my hard drive.. any faster way of doing this?... i am corrently working on the Compiler class but i need a faster approach.
Also for running likewise when i clike on the "Execute App" button.
Thanks.

These will provide you with some information
http://www.xlsoft.com/en/products/jet/index.html
http://gcc.gnu.org/java/
http://www.google.ca/search?as_q=&num=10&hl=en&ie=UTF-8&oe=UTF-8&output=advanced_search&btnG=Google+Search&as_epq=java+native+compiler&as_oq=&as_eq=&lr=&as_ft=i&as_filetype=&as_qdr=all&as_occt=any&as_dt=i&as_sitesearch=&safe=images
http://www.google.ca/search?as_q=create+java+exe&num=10&hl=en&ie=UTF-8&oe=UTF-8&output=advanced_search&btnG=Google+Search&as_epq=&as_oq=&as_eq=&lr=&as_ft=i&as_filetype=&as_qdr=all&as_occt=any&as_dt=i&as_sitesearch=&safe=images
http://search.java.sun.com/search/java/index.jsp?and=create+exe&phr=&qt=&not=&field=&since=&nh=10&col=javaforums&col=wireless&rf=0&Search.x=21&Search.y=7

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hi all
i want to start programming with JAVA
I'm new here and I don't know anything about java
can anyone can tell me where is the IDE, the environment of java
what is the different beetween JSEE and J2EE
what do i need for starting.
thanx

hi all
i want to start programming with JAVA
I'm new here and I don't know anything about java
can anyone can tell me where is the IDE, the
environment of java
what is the different beetween JSEE and J2EE
what do i need for starting.
thanxThe tutorials here on sun.com are a good place to start. Don't start with an IDE, just use a text editor and the command line for now. Don't worry about J2EE for now either just downlaod the standard JDK from this site,

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Hi SIR
It is very kind of you to give me so great informatin!
Thanks a lot!
Caton

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