While utilizing Java, we may encounter the error “Cannot find symbol”. This is a compilation error that arises when the Java compiler fails to identify a variable, method, class, or reference within the code. Java offers several methods to resolve these kinds of issues.

In this article, we shall delve into the reasons why the ‘Cannot Find Symbol’ error occurs, provide examples, and discuss the solutions for rectifying it.

Table of Contents:

• What Triggers the Java Cannot Find Symbol Error?
• Illustrations of the Java Cannot Find Symbol Error
  • Instance 1: Employing an Undeclared Variable
  • Instance 2: Variable or Method is Outside the Scope
  • Instance 3: Misnamed Variable, Method, or Class
  • Instance 4: Absent Import Statement for External Classes
• How to Resolve the “Cannot Find Symbol” Error?
• Cannot Find Symbol vs Symbol Not Found vs Cannot Resolve Symbol
• Summary

What Triggers the Java Cannot Find Symbol Error?

In Java, Cannot Find Symbol is a compile-time issue that happens for the following reasons:

• When an undeclared variable or method is utilized,
• When a variable or method is accessed outside its defined scope,
• When there is a typographical error in a variable or method name,
• When incorrect import and export declarations are used,
• When a method or variable defined in a different package is referenced.

Illustrations of the Java Cannot Find Symbol Error

Let’s investigate how this error can manifest through various examples:

Instance 1: Employing an Undeclared Variable

If a variable is referenced prior to its declaration, the compiler will not recognize it and will trigger an error.

Example Code:

var isMobile = window.innerWidth “);

editor44194.setValue(decodedContent); // Set the default text editor44194.clearSelection();

editor44194.setOptions({ maxLines: Infinity });

function decodeHTML44194(input) { var doc = new DOMParser().parseFromString(input, “text/html”); return doc.documentElement.textContent; }

// Function to copy code to clipboard function copyCodeToClipboard44194() { const code = editor44194.getValue(); // Get code from the editor navigator.clipboard.writeText(code).then(() => { jQuery(“.maineditor44194 .copymessage”).show(); setTimeout(function() { jQuery(“.maineditor44194 .copymessage”).hide(); }, 2000); }).catch(err => { console.error(“Error copying code: “, err); }); }

function runCode44194() { var code = editor44194.getSession().getValue(); jQuery(“#runBtn44194 i.run-code”).show(); jQuery(“.output-tab”).click();

jQuery.ajax({ url: “https://intellipaat.com/blog/wp-admin/admin-ajax.php”, type: “post”, data: { language: “java”, code: code, cmd_line_args: “”, variablenames: “”, action:”compilerajax” }, success: function(response) { var myArray = response.split(“~”); var data = myArray[1]; jQuery(“.output44194”).html(“

"+data+"

“); jQuery(“.maineditor44194 .code-editor-output”).show(); jQuery(“#runBtn44194 i.run-code”).hide(); } }) }

function closeoutput44194() { var code = editor44194.getSession().getValue(); jQuery(“.maineditor44194 .code-editor-output”).hide(); }

// Attach event listeners to the buttons document.getElementById(“copyBtn44194”).addEventListener(“click”, copyCodeToClipboard44194); document.getElementById(“runBtn44194”).addEventListener(“click”, runCode44194); document.getElementById(“closeoutputBtn44194”).addEventListener(“click”, closeoutput44194);

Output:

Explanation: In the code above, we attempt to print the value of number, yet we have not declared it.

to copy code to clipboard
function copyCodeToClipboard85875() {
const code = editor85875.getValue(); // Retrieve code from the editor
navigator.clipboard.writeText(code).then(() => {
// alert(“Code copied to clipboard!”);

jQuery(“.maineditor85875 .copymessage”).show();
setTimeout(function() {
jQuery(“.maineditor85875 .copymessage”).hide();
}, 2000);
}).catch(err => {
console.error(“Error copying code: “, err);
});
}

function runCode85875() {

var code = editor85875.getSession().getValue();

jQuery(“#runBtn85875 i.run-code”).show();
jQuery(“.output-tab”).click();

jQuery.ajax({
url: “https://intellipaat.com/blog/wp-admin/admin-ajax.php”,
type: “post”,

data: {
language: “java”,
code: code,
cmd_line_args: “”,
variablenames: “”,
action:”compilerajax”
},
success: function(response) {
var myArray = response.split(“~”);
var data = myArray[1];

jQuery(“.output85875”).html(“

"+data+"");
									jQuery(".maineditor85875 .code-editor-output").show();
									jQuery("#runBtn85875 i.run-code").hide();
									
								}
							})
					

						}
						
						
		function closeoutput85875() {	
		var code = editor85875.getSession().getValue();
		jQuery(".maineditor85875 .code-editor-output").hide();
		}

    // Bind event listeners to the buttons
    document.getElementById("copyBtn85875").addEventListener("click", copyCodeToClipboard85875);
    document.getElementById("runBtn85875").addEventListener("click", runCode85875);
    document.getElementById("closeoutputBtn85875").addEventListener("click", closeoutput85875);
 
    



Output:






Clarification: In the illustrated code, we have specified the method printMessage, yet we attempt to invoke printMsg, which results in an error.
```javascript
 to duplicate code to the clipboard
    function duplicateCodeToClipboard85875() {
        const code = editor85875.getValue(); // Retrieve code from the editor
        navigator.clipboard.writeText(code).then(() => {
          //  alert("Code has been copied to clipboard!");
			
			jQuery(".maineditor85875 .copymessage").show();
			setTimeout(function() {
				jQuery(".maineditor85875 .copymessage").hide();
			}, 2000);
        }).catch(err => {
            console.error("Failed to copy code: ", err);
        });
    }

 
	function executeCode85875() {	

var code = editor85875.getSession().getValue();




jQuery("#runBtn85875 i.run-code").show();
		 jQuery(".output-tab").click();
		
			jQuery.ajax({
								url: "https://intellipaat.com/blog/wp-admin/admin-ajax.php",
								type: "post",
								
								data: {
									language: "java",
									code: code,
									cmd_line_args: "",
									variablenames: "",
									action:"compilerajax"
								},
								success: function(response) {
									var myArray = response.split("~");
									var data = myArray[1];
								
									jQuery(".output85875").html("
"+data+"");
									jQuery(".maineditor85875 .code-editor-output").show();
									jQuery("#runBtn85875 i.run-code").hide();
									
								}
							})
					

						}
						
						
		function dismissOutput85875() {	
		var code = editor85875.getSession().getValue();
		jQuery(".maineditor85875 .code-editor-output").hide();
		}

    // Bind event handlers to the buttons
    document.getElementById("copyBtn85875").addEventListener("click", duplicateCodeToClipboard85875);
    document.getElementById("runBtn85875").addEventListener("click", executeCode85875);
    document.getElementById("closeoutputBtn85875").addEventListener("click", dismissOutput85875);
 
    



Result:






Clarification: In the provided code, we have defined a method called printMessage(), but we are attempting to call a method named printMsg(), which is a misspelling of the original method. This is the reason behind the error we encounter.







Instance 4: Absence of Import Statement for External Classes



When a class from a different package is utilized without an import statement, the compiler will fail to recognize it and will generate an error.



Sample Code:




			

				Java 
			
			

				

					
					

						
							 Duplicate Code
						
									 Execute Code
									
								
				

						

					
				
				

				Code Copied!
				

					

						

							 Close Code
						
						

					
				
			
		
  




Result:






Clarification: In the above code, we attempt to declare an ArrayList, however, we have not imported the ArrayList package.



To rectify the code above, we must include the following import statements at the beginning of the Java file:



import java.util.List;
import java.util.ArrayList;'

How to Resolve the Error “Cannot Find Symbol”?
```Find Symbol’ utilizing the following optimal practices:

• Inspect for Errors: Prior to executing the program, ensure that the variable, method, and class names are accurately spelled.
• Confirm Scope: It is essential to verify that the variable or method is declared within the appropriate scope and is accessible where it is invoked.
• Import Necessary Classes: When utilizing a class from a different package, you need to import that package into your current file.
• Declare Variables Prior to Use: Always ensure a variable is declared before it is referenced in your code.
• Examine for Case Sensitivity: Java is sensitive to case; therefore, ensure that identifiers match precisely as declared.
• Compile All Files: If you're dealing with multiple files, ensure all dependent classes are correctly compiled before running.
• Correct Constructor and Method Invocations: You need to confirm that method and constructor invocations are using the proper parameters and conform to the expected signatures.

Cannot Find Symbol vs Symbol Not Found vs Cannot Resolve Symbol

Below are the primary distinctions among the errors: ‘Cannot Find Symbol,’ ‘Symbol Not Found,’ and ‘Cannot Resolve Symbol’.

Conclusion

In this blog so far, we have explored the causes behind the error “Cannot Find Symbol” and how we can rectify it through various best practices. By thoroughly inspecting for errors, applying appropriate variable scope, and managing imports and exports accurately, we can evade this error.

If you aim to excel in all aspects of the Java programming language, you might consider our Java course.

Cannot find symbol or Cannot resolve symbol Error – FAQs

The post What Does a Cannot find symbol or Cannot resolve symbol Error Mean? first appeared on Intellipaat Blog.