Cannot run Java HelloWorld program

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Cannot run Java HelloWorld program

Asked by toooki

at 2024-07-27 23:30:35

Point:500 Replies:20 POST_ID:829132USER_ID:12024

Topic:

Java Programming Language;;Miscellaneous Programming

I cannot run a java program on a Linux server, which has java installed. I can compile but cannot run the program. I have the error as below. Could you please suggest how to fix it? Thanks a lot.
$ which java
/usr/bin/java
$ java -version
java version "1.6.0_21"
Java(TM) SE Runtime Environment (build 1.6.0_21-b06)
Java HotSpot(TM) 64-Bit Server VM (build 17.0-b16, mixed mode)
$cat HelloWorld.java
public class HelloWorld {

public static void main(String[] args) {
System.out.println("Hello, World");
}

}
$javac HelloWorld.java
$ls HelloWorld.class
HelloWorld.class
$java HelloWorld
Exception in thread "main" java.lang.NoClassDefFoundError: HelloWorld
Caused by: java.lang.ClassNotFoundException: HelloWorld
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: HelloWorld. Program will exit.

Expert: CEHJ replied at 2024-07-29 09:09:56

:)

fyi, where you have reasonably complex classpaths and you don't want/need the overhead of an IDE, get used to using Ant at the command line - it's lightweight and powerful

Author: toooki replied at 2024-07-29 08:57:46

Thank you. I later realized that.
I anyway recovered from the most problematic part (compile and run).
Thanks a lot.

Expert: CEHJ replied at 2024-07-29 01:29:04

I tried the above and got the small error:

That means PutMerge is expecting at least one argument to be passed to the app

Author: toooki replied at 2024-07-29 01:11:49

Thank you. Yes it is a code issue that I will debug and fix.

The compilation works!!! Many thanks ..

java -cp '.:/usr/lib/hive/lib/*:/usr/lib/hadoop/*' PutMerge
The above worked, The syntax is hard to me but it worked..which is great, So I think the hadoop libraries that I have is good to compile..

Thank you.

Expert: duncanb7 replied at 2024-07-29 00:10:00

PutMerge that is your writing code ? it seems it is code issue

Take a look this have similar error, ArrayIndexOutOfBoundsException,and its tutorial at this site
http://examples.javacodegeeks.com/java-basics/exceptions/java-lang-arrayindexoutofboundsexception-how-to-handle-array-index-out-of-bounds-exception/

Duncan

Author: toooki replied at 2024-07-28 23:32:28

Thank you.
I searched for the jar files and all the files are there under $HADOOP_HOME directory. I have attached the output screenshot of the ls -l on that directory.
It is hard for me to reinstall apache hadoop there as it is running the hadoop production server.

I tried the above and got the small error:
$ java -cp '.:/usr/lib/hive/lib/*:/usr/lib/hadoop/*' PutMerge
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0
at PutMerge.main(PutMerge.java:15)
$

hadoop-home.JPG

192 KB
hadpp_home

Accepted Solution

Expert: CEHJ replied at 2024-07-28 15:11:25

250 points EXCELLENT

Try

java -cp '.:/usr/lib/hive/lib/*:/usr/lib/hadoop/*' PutMerge

1:

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Expert: duncanb7 replied at 2024-07-28 10:33:11

Why not reinstall apache hadoop and search its site from google ?

Duncan

Expert: duncanb7 replied at 2024-07-28 10:22:51

I am not quite sure where it is, could you use linux command to search it ?

it is at I guess only
$HADOOP_HOME/share/hadoop/common/hadoop-common-2.2.0.jar

Author: toooki replied at 2024-07-28 10:20:08

Thank you.

I do not see hadoop-common-*.jar file under $HADOOP_HOME. (I attached the screenshot)

I tried:
$CLASSPATH=$(ls $HIVE_HOME/lib/hive-serde-*.jar):$(ls $HIVE_HOME/lib/hive-exec-*.jar):$(ls $HADOOP_HOME/hadoop*.jar)
$echo $CLASSPATH
/usr/lib/hive/lib/hive-serde-0.7.1-cdh3u4.jar:/usr/lib/hive/lib/hive-exec-0.7.1-cdh3u4.jar:/usr/lib/hadoop/hadoop-0.20.2-cdh3u4-ant.jar /usr/lib/hadoop/hadoop-0.20.2-cdh3u4-core.jar /usr/lib/hadoop/hadoop-0.20.2-cdh3u4-examples.jar /usr/lib/hadoop/hadoop-0.20.2-cdh3u4-test.jar /usr/lib/hadoop/hadoop-0.20.2-cdh3u4-tools.jar /usr/lib/hadoop/hadoop-ant-0.20.2-cdh3u4.jar /usr/lib/hadoop/hadoop-ant.jar /usr/lib/hadoop/hadoop-core-0.20.2-cdh3u4.jar /usr/lib/hadoop/hadoop-core.jar /usr/lib/hadoop/hadoop-examples-0.20.2-cdh3u4.jar /usr/lib/hadoop/hadoop-examples.jar /usr/lib/hadoop/hadoop-test-0.20.2-cdh3u4.jar /usr/lib/hadoop/hadoop-test.jar /usr/lib/hadoop/hadoop-tools-0.20.2-cdh3u4.jar /usr/lib/hadoop/hadoop-tools.jar
java -classpath .:${CLASSPATH} PutMerge
Exception in thread "main" java.lang.NoClassDefFoundError: /usr/lib/hadoop/hadoop-0/20/2-cdh3u4-core/jar
Caused by: java.lang.ClassNotFoundException: .usr.lib.hadoop.hadoop-0.20.2-cdh3u4-core.jar
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: /usr/lib/hadoop/hadoop-0.20.2-cdh3u4-core.jar. Program will exit.

hadoop-home.JPG

60 KB
hadoop_home

Expert: duncanb7 replied at 2024-07-28 10:07:11

I don't see you include $HADOOP_HOME/hadoop-common-*.jar

Author: toooki replied at 2024-07-28 09:49:17

Thank you but I still get the error.

I compileted with the command:
$CLASSPATH=$(ls $HIVE_HOME/lib/hive-serde-*.jar):$(ls $HIVE_HOME/lib/hive-exec-*.jar):$(ls $HADOOP_HOME/hadoop-core-*.jar)
$javac -cp $CLASSPATH PutMerge.java
$ls PutMerge.class
PutMerge.class

Now I tried:

$CLASSPATH=$(ls $HIVE_HOME/lib/hive-serde-*.jar):$(ls $HIVE_HOME/lib/hive-exec-*.jar):$(ls $HADOOP_HOME/hadoop-core-*.jar)$echo $CLASSPATH/usr/lib/hive/lib/hive-serde-0.7.1-cdh3u4.jar:/usr/lib/hive/lib/hive-exec-0.7.1-cdh3u4.jar:/usr/lib/hadoop/hadoop-core-0.20.2-cdh3u4.jar$java -classpath .:${CLASSPATH} PutMergeException in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/fs/FileSystemCaused by: java.lang.ClassNotFoundException: org.apache.hadoop.fs.FileSystem        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)        at java.security.AccessController.doPrivileged(Native Method)        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)        at java.lang.ClassLoader.loadClass(ClassLoader.java:248)Could not find the main class: PutMerge.  Program will exit.

1:2:3:4:5:6:7:8:9:10:11:12:13:

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If I try:

$java -cp $($HADOOP_HOME/bin/hadoop classpath):. PutMergejava -cp $($HADOOP_HOME/bin/hadoop classpath):. PutMerge14/07/28 16:33:40 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable14/07/28 16:33:40 INFO security.JniBasedUnixGroupsMapping: Bailing out since native library couldn't be loadedException in thread "main" java.lang.ExceptionInInitializerError        at java.lang.Class.forName0(Native Method)        at java.lang.Class.forName(Class.java:247)        at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:951)        at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1002)        at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1028)        at org.apache.hadoop.security.Groups.<init>(Groups.java:48)        at org.apache.hadoop.security.Groups.getUserToGroupsMappingService(Groups.java:137)        at org.apache.hadoop.security.UserGroupInformation.initialize(UserGroupInformation.java:251)        at org.apache.hadoop.security.UserGroupInformation.ensureInitialized(UserGroupInformation.java:229)        at org.apache.hadoop.security.UserGroupInformation.isSecurityEnabled(UserGroupInformation.java:307)        at org.apache.hadoop.security.UserGroupInformation.getLoginUser(UserGroupInformation.java:536)        at org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:519)        at org.apache.hadoop.fs.FileSystem$Cache$Key.<init>(FileSystem.java:1717)        at org.apache.hadoop.fs.FileSystem$Cache$Key.<init>(FileSystem.java:1710)        at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:1578)        at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:228)        at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:111)        at PutMerge.main(PutMerge.java:12)Caused by: java.lang.RuntimeException        at org.apache.hadoop.security.JniBasedUnixGroupsMapping.<clinit>(JniBasedUnixGroupsMapping.java:44)        ... 18 more

1:2:3:4:5:6:7:8:9:10:11:12:13:14:15:16:17:18:19:20:21:22:23:24:25:26:27:

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Now if I try:

$CLASSPATH=$(ls $HIVE_HOME/lib/hive-serde-*.jar):$(ls $HIVE_HOME/lib/hive-exec-*.jar):$(ls $HADOOP_HOME/hadoop-core-*.jar)$java -cp $($CLASSPATH classpath):. PutMerge-bash: /usr/lib/hive/lib/hive-serde-0.7.1-cdh3u4.jar:/usr/lib/hive/lib/hive-exec-0.7.1-cdh3u4.jar:/usr/lib/hadoop/hadoop-core-0.20.2-cdh3u4.jar: No such file or directoryException in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/fs/FileSystemCaused by: java.lang.ClassNotFoundException: org.apache.hadoop.fs.FileSystem        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)        at java.security.AccessController.doPrivileged(Native Method)        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)        at java.lang.ClassLoader.loadClass(ClassLoader.java:248)Could not find the main class: PutMerge.  Program will exit.

1:2:3:4:5:6:7:8:9:10:11:12:13:

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Expert: CEHJ replied at 2024-07-28 01:22:05

$java -classpath . PutMerge

1:

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completely replaces the classpath you've already used. Since the current directory was not in that classpath (it probably should have been), you actually need

java -classpath .:${CLASSPATH} PutMerge

1:

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Expert: duncanb7 replied at 2024-07-28 00:49:58

The hadoop-common-*.jar has to be included for the org.apache.commons.configuration.Configuration class

duncan

Author: toooki replied at 2024-07-28 00:36:31

PutMerge.java code:

$cat PutMerge.javapublic class PutMerge {public static void main(String[] args) throws IOException {Configuration conf = new Configuration();FileSystem hdfs = FileSystem.get(conf);FileSystem local = FileSystem.getLocal(conf);Path inputDir = new Path(args[0]);Path hdfsFile = new Path(args[1]);try {FileStatus[] inputFiles = local.listStatus(inputDir);FSDataOutputStream out = hdfs.create(hdfsFile);for (int i=0; i<inputFiles.length; i++) {System.out.println(inputFiles[i].getPath().getName());FSDataInputStream in = local.open(inputFiles[i].getPath());byte buffer[] = new byte[256];int bytesRead = 0;while( (bytesRead = in.read(buffer)) > 0) {out.write(buffer, 0, bytesRead);}in.close();}out.close();} catch (IOException e) {e.printStackTrace();}}}

1:2:3:4:5:6:7:8:9:10:11:12:13:14:15:16:17:18:19:20:21:22:23:24:25:26:27:28:29:30:31:

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Author: toooki replied at 2024-07-28 00:36:04

Thank you.

$more /etc/*-release
CentOS release 5.5 (Final)

I tried:
$java -classpath . HelloWorld

And it worked. Thank you.

I actually simplified my question. Although HelloWorld worked, my actual code is still giving the same problem:
I tried:
$CLASSPATH=$(ls $HIVE_HOME/lib/hive-serde-*.jar):$(ls $HIVE_HOME/lib/hive-exec-*.jar):$(ls $HADOOP_HOME/hadoop-core-*.jar)
$javac -cp $CLASSPATH PutMerge.java
$java -classpath . PutMerge
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/fs/FileSystem
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.fs.FileSystem
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: PutMerge. Program will exit.

Could you please suggest why it is not running. Compilation worked without errors.
Thanks a lot.

Assisted Solution

Expert: duncanb7 replied at 2024-07-28 00:23:43

250 points EXCELLENT

Try this,

java -classpath . HelloWorld

that will work

And if possible, run command of "more /etc/*-release" to check your linux Distribution
Java just support this for Linux :

LinuxOracle Linux 5.5+Oracle Linux 6.x (32-bit), 6.x (64-bit)*Red Hat Enterprise Linux 5.5+, 6.x (32-bit), 6.x (64-bit)*Ubuntu Linux 10.04 and aboveSuse Linux Enterprise Server 10 SP2, 11.x

1:2:3:4:5:6:

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Duncan

Author: toooki replied at 2024-07-28 00:20:53

Thank you. I got these:

$uname -a
Linux snapfish.myco.com 2.6.18-194.26.1.el5 #1 SMP Tue Nov 9 12:54:20 EST 2010 x86_64 x86_64 x86_64 GNU/Linux

$cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU L5420 @ 2.50GHz
stepping : 6
cpu MHz : 2003.000
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 0
cpu cores : 4
apicid : 4
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
bogomips : 5000.17
clflush size : 64
cache_alignment : 64
address sizes : 38 bits physical, 48 bits virtual
power management:

processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU L5420 @ 2.50GHz
stepping : 10
cpu MHz : 2003.000
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
bogomips : 5000.18
clflush size : 64
cache_alignment : 64
address sizes : 38 bits physical, 48 bits virtual
power management:

processor : 2
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU L5420 @ 2.50GHz
stepping : 6
cpu MHz : 2003.000
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 1
cpu cores : 4
apicid : 5
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
bogomips : 5000.12
clflush size : 64
cache_alignment : 64
address sizes : 38 bits physical, 48 bits virtual
power management:

processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU L5420 @ 2.50GHz
stepping : 10
cpu MHz : 2003.000
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 1
cpu cores : 4
apicid : 1
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
bogomips : 5000.13
clflush size : 64
cache_alignment : 64
address sizes : 38 bits physical, 48 bits virtual
power management:

processor : 4
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU L5420 @ 2.50GHz
stepping : 6
cpu MHz : 2003.000
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 2
cpu cores : 4
apicid : 6
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
bogomips : 5000.10
clflush size : 64
cache_alignment : 64
address sizes : 38 bits physical, 48 bits virtual
power management:

processor : 5
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU L5420 @ 2.50GHz
stepping : 10
cpu MHz : 2003.000
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 2
cpu cores : 4
apicid : 2
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
bogomips : 5000.20
clflush size : 64
cache_alignment : 64
address sizes : 38 bits physical, 48 bits virtual
power management:

processor : 6
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU L5420 @ 2.50GHz
stepping : 6
cpu MHz : 2003.000
cache size : 6144 KB
physical id : 1
siblings : 4
core id : 3
cpu cores : 4
apicid : 7
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
bogomips : 5000.32
clflush size : 64
cache_alignment : 64
address sizes : 38 bits physical, 48 bits virtual
power management:

processor : 7
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Xeon(R) CPU L5420 @ 2.50GHz
stepping : 10
cpu MHz : 2003.000
cache size : 6144 KB
physical id : 0
siblings : 4
core id : 3
cpu cores : 4
apicid : 3
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
bogomips : 5000.27
clflush size : 64
cache_alignment : 64
address sizes : 38 bits physical, 48 bits virtual
power management:

Expert: duncanb7 replied at 2024-07-28 00:19:05

Try this,

java -classpath . HelloWorld

that will work

Duncan

Expert: duncanb7 replied at 2024-07-28 00:03:37

What is your linux version ? you can get it from command of "uname -f"
What is the system CPU information ? you can get it from command of "cat /proc/cpuinfo"

It may be compatibility issue between your system and Java

Duncan

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