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Can't find symbol even though class is in the same folder

I have looked at all the other stuff, mine is a compatibility issue I think, or PATH maybe. I have a bunch of classes I've been using since about 2008 and now the java command and the javac command can't find the classes even though they are in the same directory/folder. I have C:\Program Files\Java\jdk1.6.0_25\bin in the Path variable, but nothing in the Classpath. I normally have the compiled classes in the same folder with the java I'm compiling. I've been doing the same thing for 5 years! I have recompiled the lowest level class which is called WotifCat01. The compiler comes back with
WotifCat00.java:27:cannot find symbol
Symbol : WotifCat01
import java.io.*;
/** Find/replace program **/
class WotifCat00
{
private static int cnt;
private static String[][] filnamStrg={ {"Data/reftfile.txt","Data/AccumData/allreftfile.txt","","",""},
{"Data/reft1file.txt","Data/AccumData/allreft1file.txt","","",""},
{"Data/reft2file.txt","Data/AccumData/allreft2file.txt","","",""},
{"Data/reft3file.txt","Data/AccumData/allreft3file.txt","","",""},
{"Data/reft4file.txt","Data/AccumData/allreft4file.txt","","",""},
{"Data/work1file.txt","Data/AccumData/alltextsrc.txt","","",""},
{"","","","",""} };
private static String[] args1={"","","","",""};
public static void main(String[] args) {
while (filnamStrg[cnt][0] != "") {
args1[0] = filnamStrg[cnt][0];
args1[1] = filnamStrg[cnt][1];
WotifCat01 wotifCat01 = new WotifCat01();
wotifCat01.main(args1);
cnt++;
}
}
}
I've used this setup for a while and it worked fine on my laptop till now with Windows 7. I suspect something I've installed has overwritten something. This has to be really simple but I can't see it. I've removed jdk1.7.0_25 back to 1.6 but no change.
I backed up the classpath and deleted it. Now works fine. It contained IBM DB2 paths. DB2 I had installed in 2011 so discounted it, but it did have java paths in it so it must have overrode the path. I am not sure how DB2 managed to do so 2 years after install, I may have inadvertently activated something. Thanks for your input.
Neil Mc

Java file not compiling

Currently trying to work with objects in Java. Everything goes fine until I hit compile. Have been reading a couple of other questions regarding the same problem, or the same given error, and at this point I am not sure wether I am forgetting something or that I need to change my classpath.
Main Class file:
package TesterClass;
public class Tester {
public static void main(String[] args){
TesterClass firstTest = new TesterClass();
firstTest.stringPrinter();
}
}
The file that is supposed to be functioning as a package file:
package TesterClass;
public class TesterClass{
private String workingSegment;
public TesterClass(){
workingSegment = "Working";
}
public void stringPrinter(){
System.out.println(workingSegment);
}
}
The 2 files are in the same directory and I am trying to manually compile them with
"javac Tester.java". The error I get is about the fact that its having issues with the package. All help is welcome!
EDIT: Forgot to post the actual compiler error.
Tester.java:9: cannot find symbol
symbol : class TesterClass
location: class TesterClass.Tester
TesterClass firstTest;
^
Tester.java:11: cannot find symbol
symbol : class TesterClass
location: class TesterClass.Tester
firstTest = new TesterClass();
^
2 errors

Move to the top of the source tree and compile both class...
So, assuming you source files are in \Java\TesterClass, you need to start in \Java
javac TesterClass\Tester.java TesterClass\TesterClass.java
You may also want to have a quick read of Code Conventions for the Java Programming Language as packages names are suppose to be in lower case :P
Updated
I just tried...
javac TesterClass\Tester.java
And it worked fine.
Are you sure that the Tester.java and TesterClass.java are in the TesterClass directory?
Updated with running example
So, basically, I dropped you .java files into the directory \compile under the TesterClass (\compile\TesterClass) directory and compiled them using...
\compile>javac TesterClass\Tester.java
Then I run them...
\compile>java TesterClass.Tester
Working

You need to go to the top of the directory hierarchy and first compile your TesterClass and then compile your Tester. Since you have not compiled your TesterClass yet, Tester is unable to find it.
The error clearly states that its not able to find the symbol TesterClass, and the reason being TesterClass hasn't been compiled yet.
I suggest you use an IDE which does the compilation automatically for you. If you stick to manual compilation, you need to compile all the classes in the proper order.

Try changing the package name so it does not match the class name. Right now they are the same. Make it package TesterClassPackage, then import TesterClass into the file with the main() method. Even though they are in the same package sometimes you need to literally import files even though they are in the same package.

javac TesterClass\TesterClass.java TesterClass\Tester.java
will do it

Getting "class does not have a static void main method accepting String[]" error even though main signature is correct

My DrJava was working fine, but now I keep getting the folowing error whenever I run anything:
Static Error: This class does not have a static void main method accepting String[].
So it will compile OK, but then it shoots out the error . This happens even though everything I test does indeed have a public static void main(String[] args) in it. It seems like a classpath/resources type of error. I appreciate any tips
EDIT: my class
public class Test{
public static void main(String[] args){
System.out.println(" hashmap ");
}
}

There's nothing wrong with the code, so the problem must be with the environment.
Check that you're actually executing that class. Find out where the class that's executed is specified and check it's correct
Check that you're compiling the class. Maybe the code you're looking at has not been compiled and you're trying to execute an old version that was compild before you coded a main()
Check your classpath. Is the compiled class accessible in the classpath of the java command

You don't need to reinstall java, nor is it a java version issue. It may be the way that your are running the program.
To check if it is a problem with your code, do the following:
Make a new folder and put Test.java in it.
Open up Command Line Or Terminal and change to that folder .
Type javac Test.java. Test.class should be in the folder now.
If you want, open up the class with a text editor. This is what I get:
˛∫æ2
<init>()VCodeLineNumberTablemain([Ljava/lang/String;)V
SourceFile Test.java hashmap Testjava/lang/Objectjava/lang/SystemoutLjava/io/PrintStream;java/io/PrintStreamprintln(Ljava/l ang/String;)V! *∑±
% ≤∂±
Back to the command line or terminal, type java Test.
If you get an error, which you shouldn't, I don't know what to say. It should produce the string " hashmap " on to the command line or terminal.
Why re-installing Dr. Java may not work is because you may be using the same working directory, causing same run settings to be used. Dr. Java may be running an external program, one without a main method.
I think that you should install the Eclipse IDE for Java. It is much easier to get around, it looks nicer, and it runs the file or project that you are looking at currently.

Sometimes this problem happens because may be mistake in saving file.you always your file using double quotes and with the .java extension which is main class means that class containing main method.
you should save your file by class name which is public .if there is two classes and both have main method then you should save your file by class name that is public and that class will be run.As like your compiler looking for main method in public static void main(String [] args) that is contract for jvm to run a programme
so it is not able to found that main method that is static and it looking for your Dr class.java
See this Example it have two main methods and practice these kinds of question.I also got this kind of problem in starting.
public class TestFirst
{
public static void main(String [] args){
System.out.println(" TestFirst ");
}
}
class Test{
public static void main(String [] args){
System.out.println(" hashmap ");
}
}
if you save pro-gramme by "TestFirst.java" then o/p will come TestFirst if you do some mistake in main method because we have saved our programme by TestFirst then you will get error like you got.
# 2nd mistake may be this
debian#debian:~/Geany_java$ javac Test1.java
debian#debian:~/Geany_java$ java Test1
Exception in thread "main" java.util.NoSuchElementException
at java.util.StringTokenizer.nextToken(StringTokenizer.java:349)
at Test1.main(Test1.java:11)
your classpath has not set properly See above Compiling successfully but running showing same kind of error you got.Which OS is using I can guide you properly.

Check that actually your file have the .java termination nor the .dj

There is nothing wrong with the code.
It is the executing environment which might have problem. Please share the details.

Check if program compiled correctly.
Check time-stamo of .class file.
Check permissions on folder/directory where class-files are getting generated.
Check if DrJAVA has appropriate permission on the directory.
Did you create a file, compiled it with out main?
Check class-path. Might be possible that previous class file is still being found by JDK in classpath.
Try compiling .java file from cmdLine instead of editor.

As others have mentioned, your code is fine. There must be a problem with your environment. I recently experienced a similar issue when investigating and answering this question.
Basically, in that question, the code Void.class instanceof Class resulted in a compiler error because a user-made Class.class existed in the classpath, so one Class (the Java built-in java.lang.Class) didn't match with the given Class (user-made).
Something similar may be at work here. It is possible that there is a user-made String.class in your classpath. Then in your main signature, String[] args would mean an array of your String, when Dr. Java must be looking for a main method taking an array of the Java built-in String, i.e. java.lang.String[]. If you have a custom String class in your classpath (or in your project?), then the Java compiler will choose it over the built-in String. If you were to compile and run your Test class from the command line, then you would get the runtime error: Exception in thread "main" java.lang.NoSuchMethodError: main.
Following #S0urceC0ded's suggestion, you may find this when looking at Test.class in a text editor:
main([LString;)V // A user-made String class
instead of what it's supposed to be:
main([Ljava/lang/String;)V // The built-in java.lang.String class
If so, remove your own String class (at least the .class file, but also the .java file so the .class file isn't re-created) from the classpath, and compile and run your Test class again.
Without a look at your environment, I can't tell for sure that this is the issue. But it can explain it.

If you are using Dr.Java as IDE, then you need to make sure that the main class containing 'public static void main' should be at the very top of your program. Otherwise Dr.Java throws this error during runtime.

"Error: Could not find or load main class My.class"

Im using Java SDK 1.7 on Windows 7 via cmd.exe . Up until a few hours ago everything was working correctly when suddenly I was unable to run my compiled class files, consistently presented with the error in the title.
I seem to be able to compile my My.java file however I am unable to run the resulting class file (My.class). I am constantly given the error "Error: Could not find or load main class My.class". I have tried this with multiple other class files all resulting in the same problem.
My 'Path' environment variable is set to "C:\Program Files (x86)\Java\jdk1.7.0_05\bin" if you were wondering
I have tried reinstalling, creating and setting a classpath variable (no luck), and even directly using the
java -cp . My.class
command.
I have tried these posts all to no avail, hence why I'm posting:
Error: Could not find or load main class
Error: Could not find or load main class- Novice
Could not find or load main class
Java 1.7.0_03 Error: Could not find or load main class
If it makes any difference my code is :
import javax.swing.JOptionPane;
class My {
public static void main(String[] args) {
final double x = 3.2;
int i = (int)x;
double m = 0;
if (x < 4) {
String saySomething = JOptionPane.showInputDialog(i);
System.out.println(saySomething);
}
else {
String saySomething = JOptionPane.showInputDialog(i);
System.out.println("Hello World");
}
while (m < 10) {
System.out.print(" While Loop ");
m++;
};
for (i=1; i < 10; i++) {
System.out.println("For Loop");
};
}
}

You should specify the classname instead of the file of the class to load. The difference is a simple matter of removing the .class extension.

I would use an IDE and you shouldn't get these issues. Compile and run is just a click of the mouse.
BTW to run your program from the command line
java -cp . My
You don't add .class

Position yourself in a directory of your project (you need to have src and bin directories there, assuming you keep sources in src and binaries in bin)
java -cp bin My

I myself was facing the same problem. It was happening because I was being remiss in typing the name of the class properly. In my instance, I was typing
java doubler
instead of
java Doubler

Java package - class not found, same directory

I have two Java classes "giveMyOb" and "dataConn" declared in the same directory. Both are public classes. "giveMyOb" has a static method "getMine()". Inside dataConn, I called the static method as
giveMyOb.getMine();
When I try to compile dataConn.java, the following error is returned.
"Cannot find symbol
symbol: variable giveMyOb
location : class dataConn
giveMyOb.getMine(); "
It used to work earlier. But is not working now. Why is that?
Additional Information: JDK 1.6. Windows 7. 64 bit.
Update(30 days after the question): When compiled from Eclipse, the classes are referenced and it works. But the same won't work when compiling from command line. I was unable to figure out the reason and nothing logical comes to my mind!

javac -classpath . *.java
ought to create both .class files at the same time. It's more complicated by packages. I'm assuming you have none.
Learn the Sun Java coding conventions. You aren't following them with those class names. They should start with a capital letter.

Try this:
giveMyOb.java
public class giveMyOb {
public static String getMine() {
return "Yay, it works!";
}
}
dataConn.java
public class dataConn {
public static void main(String[] args) {
System.out.println(giveMyOb.getMine());
}
}
Then compile it all:
javac *.java
and run the main class:
java -cp . dataConn
// output: Yay, it works!
Note that Java's coding conventions recommend class names start with a capital.
If "it" still doesn't work, try removing the .class files manually then recompile again.