Understanding Javas Cannot Find Symbol Error Message

When a Java program is being compiled, the compiler creates a list of all the identifiers in use. If it cant find what an identifier refers to (e.g., there is no declaration statement for a variable) it cannot complete the compilation. This is what the cannot find symbol error message is saying—the compiler  doesnt have enough information to piece together what the Java code is intended to execute. Possible Causes For the  Cannot Find Symbol Error Although the Java source code contains other things like keywords, comments, and operators, the Cannot Find Symbol error references the name of a specific package, interface, class, method or variable. The compiler needs to know what every identifier references. If it doesnt, the code is basically looking for something that the compiler doesnt yet comprehend. Some possible causes for the Cannot Find Symbol Java error include: Trying to use a variable without declaring it.Misspelling a class or method name.  Remember that  Java is case sensitive  and spelling errors are not  corrected for you. Also, underscores may or may not be necessary, so watch out for code that use them when they shouldnt be used or vice versa.The parameters used do not match a methods signature.The packaged class has not been referenced correctly using an import declaration.Identifiers  look  the same but are actually different. This problem can be hard to spot, but in this case, if the source files use UTF-8 encoding, you may be using some identifiers as if theyre identical but really theyre not because they simply appear to be spelled the same.Youre looking at the wrong source code. It may seem hard to believe that youre reading a different source code than the one producing the error, but its definitely possible, and especially for new Java programmers. Check file names and version histories carefully.You forgot a new, like this:  String s String();, which should be  String s new String(); Sometimes, the error arises from a combination of problems. Therefore, if you fix one thing, and the error persists, check for different problems still affecting your code. For example, its possible that you are trying to use an undeclared variable and when you fix it, the code still contains spelling errors. Example of a Cannot Find Symbol Java Error Lets use this code as an example: This code will cause a cannot find symbol error because the System.out class does not have a method called â€Å"prontln†: The two lines below the message will explain exactly what part of the code is confusing the compiler. Mistakes like capitalization mismatches are often flagged in a dedicated integrated development environment. Although you can write your Java code in any text editor, using IDEs and their associated linting tools reduces typos and mismatches. Common Java IDEs include Eclipse and NetBeans.