Java cannot find symbol hashmap

«error: cannot find symbol HashMap» [duplicate]

The sample HashMap implementation code fails to compile with the error: Here is the code: I have read the JavaDocs on the hashmap class, and confirmed that is a valid HashMap method to replace a value for a specified key. a in below fashion : I am using an online complier and have searched a lot, i found that my way of declaration is correct but something else is popping up the error Below is the error What i need help in : m just trying to get the basic of creating a hashmap and inserting some key and value in it, but above error stopped me in very first step. any help in solving this is appreciated!!

«error: cannot find symbol HashMap» [duplicate]

Trying to create ( or rather learn ) a HashMap in below fashion :

public class Demo < public static void main(String args[])< System.out.println("============Starting Hashmap============"); //hashmap portion HashMapmyMap = new HashMap(); System.out.println("============Ending Hashmap============"); > > 

I am using an online complier and have searched a lot, i found that my way of declaration is correct but something else is popping up the error
Below is the error

Demo.java:8: error: cannot find symbol HashMap myMap = new HashMap(); ^ symbol: class HashMap location: class Demo Demo.java:8: error: cannot find symbol HashMap myMap = new HashMap(); ^ symbol: class HashMap location: class Demo 2 errors 

What i need help in : m just trying to get the basic of creating a hashmap and inserting some key and value in it, but above error stopped me in very first step. any help in solving this is appreciated!! 🙂

You need to import the HashMap into the class

import java.util.HashMap; public class Demo < public static void main(String args[])< System.out.println("============Starting Hashmap============"); //hashmap portion HashMapmyMap = new HashMap(); System.out.println("============Ending Hashmap============"); > > 

you need to import the HashMap to avoid the compile error

java.util.HashMap map = new java.util.HashMap<>();

Use this if you can’t import java.util.HashMap;

Java compilation error: cannot find symbol, [ERROR] WebStatusMonitor.java:[121,66] cannot find symbol symbol: method getOrDefault(java.lang.String,java.lang.Double) What are the differences between a HashMap and a Hashtable in Java? 7455. Is Java «pass-by-reference» or «pass-by-value»? 3788. How do I efficiently iterate over each entry in a Java Map?

Java: Cannot find symbol error on Map, HashMap

I’m trying to run this code:

import java.util.*; public class ScanReg < public Map> scanMap = new HashMap>(); > 

import java.util.*; public class NxtStart

This keeps giving me the following error:

.\ScanReg.java:6: error: cannot find symbol public Map> scanMap = new HashMap>(); ^ symbol: class Map location: class ScanReg .\ScanReg.java:6: error: cannot find symbol public Map> scanMap = new HashMap>(); ^ symbol: class HashMap location: class ScanReg 2 errors 

Can somebody please tell me why?

You’re possibly compiling using Java 1.4 and using generics ( only available from 1.5 onwards ).

You need to declare your inner class as static

public static class ScanReg <> 

Else, put in different java file and import ScanReg.

Hashmap — Java cannot find Symbol, Find centralized, trusted content and collaborate around the technologies you use most. Learn more

HashMap types cannot find symbol

I have a class with some HashMap types:

private class XmlHandler extends DefaultHandler < private HashMapAttribs; private HashMap >FragmentNode; private HashMap > ActivityNode; 

When compiling, I’m receiving this errors:

cannot find symbol FragmentNode and Attribs. 

If I modify declarations inserting raw types i.e. changing HashMap to HashMap> compiler stops to complain.

Do I need to do this? Java doesn’t understand type declarations like these?

FragmentNode and Attribs are not a types, its a variables, you can’t specify variables as types to HashMap .

You could do this instead:

private HashMap>> FragmentNode; 

Or you could create a class that has Attribs HashMap just like:

public class Attribs < private HashMapAttribs; > 

 private HashMap> FragmentNode; 

Seems like you’re mixing types with attributes.

If you want a specific hierarchy like this, you should define new classes:

class Attribs extends HashMap <> class FragmentNode extends HashMap> <> class ActivityNode extends HashMap> <> 

Then you can create members like this:

private class XmlHandler extends DefaultHandler

HashMap for noobs — compilator «cannot find symbol, I’m new to programming (java) and learning, thanks for alle the answares. When changing the HashMap name to komm, the compilator cant find variabel komm in Komm enKom = (Komm) komm.get (kommune); – user265767. Feb 14, 2010 at 22:17. @MatrixFrog — you’re right, I got confused between the …

Cannot find symbol — HashMap .replace() method

I am practicing using HashMap in JAVA from a tutorial. The sample HashMap implementation code fails to compile with the error:

DictionaryPractice.java:57: error: cannot find symbol shoppingList.replace("Bread", Boolean.FALSE); symbol: method replace(String,Boolean) location: variable shoppingList of type Map

import java.util.HashMap; import java.util.Map; public class DictionaryPractice < public static void main(String[] args) < MapshoppingList = new HashMap(); // Put some stuff in dictionary shoppingList.put("Ham", true); shoppingList.put("Bread", Boolean.TRUE); shoppingList.put("Oreos", Boolean.TRUE); shoppingList.put("Eggs", Boolean.FALSE); shoppingList.put("Sugar", false); // Retrieve items System.out.println(shoppingList.get("Ham")); System.out.println(shoppingList.get("Oreos")); // Remove things shoppingList.remove("Eggs"); // Replace values for a certain key shoppingList.replace("Bread", Boolean.FALSE); > > 

I have read the JavaDocs on the hashmap class, and confirmed that .replace is a valid HashMap method to replace a value for a specified key. However, I keep getting the cannot find symbol error . Your kind help will be appreciated. Sorry for the basic question.
I am using jEdit Text Editor with the Compile plugin installed on a MacOSX Yosemite.

The method replace(K,V) in the Map interface is a new method introduced in Java 8.

Apparently, you are compiling your code with Java 7 or earlier.

Two possible solutions are:

1. Download a Java 8 JDK for Mac OS X and use that to compile your code.
2. Replace the replace with put . The method replace is a convenience method used when you don’t want the new value to be placed in the map if the key doesn’t have some value beforehand, similar to:

if ( shoppingList.contains("Bread") )

Java cannot find symbol, 1 Answer. Sorted by: 0. verhuur is a HashSet, so in order to call the getBegintijd () method of your Verhuur class you must obtain an element from the HashSet. For example, the following code will call the getBegintijd () method for the first element returned by the Set ‘s iterator :

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Cannot find symbol Java

In this post, we will see how to solve Cannot find symbol in java.

You will get this error when you have declared something that compiler does not understand. The compiler creates list of identifiers when you compile any program. If compile can not understand any of the identifiers, you will get this error.

This error generally means the compiler does not recognize any identifier and can not figure out what it means.

Let’s understand with a very basic example.

You will get below compilation error.

CannotFindSymbolMain.java:11: error: cannot find symbol
division = a/ b;
symbol: variable division
location: class CannotFindSymbolMain
CannotFindSymbolMain.java:12: error: cannot find symbol
System.out.println(division);
symbol: variable division
location: class CannotFindSymbolMain
2 errors

Did you understand the issue?
We are getting this error because we did not declare division before using it.
You need to change line 11 to:

This will resolve above compilation error.

There can be multiple reasons for this error.

1. You forgot to declare any variable
2. You misspelled any methodname , class, variable or interface. Please note that java is case sensitive language, so division and Division will be not be considered same.
3. You did not import any class correctly
4. You forgot new keyword while initializing an object.

As you can see, there can be multiple reasons for this error. You need to figure out what can be the reason for this error in your program. In most of the cases, this error is due to either the undeclared variable or misspelled identifier .

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help, cannot find symbol — variable (using hashmaps)

posted 14 years ago

Hi, I’m having a problem trying to print the integers in the arrays stored in populateStation onto seperate lines using printAreasAndFrequencies(). It brings up the error «cannot find symbol — variable northList». Also I need to ommit the [] from the prinln. Any pointers in the right direction would be great

public class Station
// instance variables for class Station
private String name;
private HashMap frequenciesByArea;

//
/**
* Constructor for objects of class Station
*/
public Station(String RadioName)
name = RadioStationName;
frequenciesByArea = new HashMap();
>
/**
* Getter Methods for name and FrequenciesByArea
*/

public String getName()
return this.name;
>

public HashMap getfrequenciesByArea()

/**
*The method for Station to populate frequencies by area
*/

public void populateStation (Integer[] north, Integer[] south,Integer[] east, Integer[] west)
Arrays.sort(north);
List northList = new ArrayList(Arrays.asList(north));

Arrays.sort(south);
List southList = new ArrayList(Arrays.asList(south));

Arrays.sort(east);
List eastList = new ArrayList(Arrays.asList(east));

Arrays.sort(west);
List westList = new ArrayList(Arrays.asList(west));

frequenciesByArea.put(«North»,northList);
frequenciesByArea.put(«South»,southList);
frequenciesByArea.put(«East»,eastList);
frequenciesByArea.put(«West»,westList);

/**
*A public instance method that print the radio name & related Areas & frequencies to the display PAne
*/

public void printAreasAndFrequencies()

System.out.println(name);
System.out.println(«north south east west clear»>

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