java.lang.numberformatexception: invalid double: " "

com.google.gson.jsonsyntaxexception: java.lang.numberformatexception: invalid double: ""
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at java lang double parsedouble double java 301
java lang stringtoreal invalidreal stringtoreal java 63

getting an error of invalid Double java.lang.numberformatexception invalid double: "" what is the reason for this

Activity 1

package com.example.solarcalculator;

        import android.os.Bundle;
        import android.widget.Button;
        import android.annotation.SuppressLint;
        import android.app.Activity;
        import android.view.Menu;
        import android.view.View;
        import android.view.View.OnClickListener;
        import android.widget.EditText;
        import android.app.AlertDialog;
        import android.content.Intent;

        @SuppressLint("UseValueOf")
        public class MainActivity extends Activity {
            private EditText input1;
            private EditText input2;
            private EditText input3;
            private EditText input4;
            private EditText input5;
            private MainActivity mContext;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mContext = this;
        setContentView(R.layout.activity_main);

        input5 = (EditText) findViewById(R.id.input5);
        Button button1 = (Button) findViewById(R.id.button1);
        input4 = (EditText) findViewById(R.id.input4);
        input1 = (EditText) findViewById(R.id.input1);
        input2 = (EditText) findViewById(R.id.input2);
        input3 = (EditText) findViewById(R.id.input3);
        button1.setOnClickListener(new OnClickListener() {

            @SuppressWarnings("unused")
            private AlertDialog show;

            @SuppressLint("UseValueOf")
            @Override
            public void onClick(View arg0) {
                if (  (input4.getText().toString() == " ") 
                        || (input4.getText().length() ==0) ||
                                                (input5.getText().length() == 0)                         
                        || (input5.getText().toString() == " ")){
                show = new      AlertDialog.Builder(mContext).setTitle("Error")
                            .setMessage("Some inputs are empty")
                            .setPositiveButton("OK", null).show();
                }
    else if ((input1.getText().length() != 0) &&
        (input3.getText().length() ==0) && (input2.getText().length() ==    0)){
                     double w = new Double(input3.getText().toString());
                     double t = new Double(input4.getText().toString());
                     double x = new Double(input5.getText().toString());
                     float e = 7;
                     double num = 1000*x;
                     double den = w*t*e;
                     double payback = num/den;
                     double money = w*t*e/1000;
         Intent intent = new Intent(MainActivity.this, Power.class);
                     intent.putExtra("payback", payback);
                     intent.putExtra("money", money);
                     startActivity(intent);

                }
    else if ((input1.getText().length() == 0) &&   (input3.getText().length() != 0) &&
                                (input2.getText().length() != 0)){
                     double t = new    
                                     Double(input4.getText().toString());
                     double x = new Double(input5.getText().toString());
                     double v = new Double(input2.getText().toString());
                     double i = new Double(input3.getText().toString());
                     float e = 7;
                     double num = 1000*x;
                     double den = v*i*t*e;
                     double payback = num/den;
                     double money = v*i*t*e/1000;
             Intent intent = new Intent(MainActivity.this, Power.class);
                     intent.putExtra("payback", payback);
                     intent.putExtra("money", money);
                     startActivity(intent);

                }
                else {
                    double t = new Double(input4.getText().toString());
                     double x = new Double(input5.getText().toString());
                     double v = new Double(input2.getText().toString());
                     double i = new Double(input3.getText().toString());
                     float e = 7;
                     double num = 1000*x;
                     double den = v*i*t*e;
                     double payback = num/den;
                     double money = v*i*t*e/1000;
               Intent intent = new Intent(MainActivity.this, Power.class);
                     intent.putExtra("payback", payback);
                     intent.putExtra("money", money);
                     startActivity(intent);

                }
            }
        });

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

       }

Activity2

package com.example.solarcalculator;

    import android.annotation.SuppressLint;
    import android.app.Activity;
    import android.os.Bundle;
    import android.widget.TextView;
   @SuppressLint("NewApi")
     public class Power extends Activity {

private double money;
private double payback;

@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.power);
    payback = getIntent().getDoubleExtra("payback",0);
    money = getIntent().getDoubleExtra("money", 0);
    TextView pay = (TextView) findViewById(R.id.textView2);
    String payback1 = Double.toString(payback);
    pay.setText(payback1);
    TextView mon = (TextView) findViewById(R.id.textView4);
    String money1 = Double.toString(money);
    mon.setText(money1);

     }
    }

I am getting java.lang.numberformatexception invalid double: "" error in logcat anyone please help

The reason is, that "" is not a valid double. You need to test the String before or catch such exceptions

double w;

try {
    w = new Double(input3.getText().toString());
} catch (NumberFormatException e) {
    w = 0; // your default value
}

java.lang.NumberFormatException: Invalid double: "" at java.lang , try { inp = Double.valueOf(fromInput.getText().toString()); } catch ( NumberFormatException e) { inp = 0; }. The value of the double depends on the language of the device. For example, for devices in french the number 0.179927 becomes 0,179927 which will always throw a NumberFormatException when parsing it to double because of the comma. You need to change the separator from a comma to a point.

The value of the double depends on the language of the device.For example, for devices in french the number 0.179927 becomes 0,179927 which will always throw a NumberFormatException when parsing it to double because of the comma.

You need to change the separator from a comma to a point. You can change the separator either by setting a locale or using the DecimalFormatSymbols.

If you want the grouping separator to be a point, you can use a european locale:

NumberFormat nf = NumberFormat.getNumberInstance(Locale.GERMAN);
DecimalFormat df = (DecimalFormat)nf;

Alternatively you can use the DecimalFormatSymbols class to change the symbols that appear in the formatted numbers produced by the format method. These symbols include the decimal separator, the grouping separator, the minus sign, and the percent sign, among others:

DecimalFormatSymbols otherSymbols = new DecimalFormatSymbols(currentLocale);
otherSymbols.setDecimalSeparator(',');
otherSymbols.setGroupingSeparator('.'); 
DecimalFormat df = new DecimalFormat(formatString, otherSymbols);

java.lang.NumberFormatException: Invalid double, The value of the double depends on the language of the device. For example, for devices in french the number 0.179927 becomes 0,179927 which will always� Invalid double: "". you are parsing onCreate() value without putting any default value so the exception. final double gpaDouble = Double.parseDouble(gpaString); because "" (empty String is not Double)

You should do as below. Put it inside a try catch block

   double w = new Double(input3.getText().toString());

Caused by: java.lang.NumberFormatException: Invalid double , in android project I has: double newAmountIntValueAsDouble = Double. parseDouble(newAmountValueAsString); but I get error: 12-30� Your problem is that the variable or resource from which you want to get value is null and so it is saying that " " is not double. If you are getting value from fromInput.getText().toString() then fromInput has no value and thus null can't be cast to double.

Better to also test for .equals("") along with null.

Consider you have an afterTextChanged listener on an EditText. When you back press and clear the entered text, it'll pass != null, but still have "".

This worked for me:

    double myDouble;

    String myString = ((EditText) findViewById(R.id.editText1)).getText().toString();

    if (myString != null && !myString.equals("")) {
        myDouble = Double.valueOf(myString);
    } else {
        myDouble = 0;
    }

Why does java.lang.NumberFormatException: Invalid double: keep , Why does java.lang.NumberFormatException: Invalid double: keep appearing? Post by: Klarisk Cersul , Greenhorn. Sep 18, 2019 10:37:10. What I needed is for � In this tutorial, we shall recreate the scenario for java.lang.NumberFormatException to happen, and explain how to fix this exception in detail. Java NumberFormatException The exception is thrown by many constructors/methods in the classes of java.lang package.

Basically, you need to test whether the string that you want to convert into double is empty or not.

If it is empty, then you can just initialise it with some value and then proceed further.

For example:

if(myString.isEmpty()){
myString = ""+0.0;
}
double answer = Double.parseDouble(myString);

java.lang.NumberFormatException: Invalid double: "Users", Hi, i send a request and get a response with error: help me why this error occur? java.lang.NumberFormatException: Invalid double: “Users”� We can convert a String to a primitive double using the Double.parseDouble method or to a wrapped Double class using the Double.valueOf. When both methods receive an invalid number as argument, a java.lang.NumberFormatException will be thrown. Convert a String to double using Double.parseDouble

Android Question - Invalid double: "null" after updating , java.lang.NumberFormatException: Invalid double: "null". upload_2018-1-10_4- 51-23.png. executing the assignment LastVersion = Version(0)� The abstract Number class is the core superclass that is used to represent numeric values which can be converted into the primitive types of byte, double, float, int, long, and short. As such, Java throws a java.lang.NumberFormatException when a failed attempt is made to convert into one of those types.

android, try { inp = Double.valueOf(fromInput.getText().toString()); } catch ( NumberFormatException e) { inp = 0; } text. Answer: A Java NumberFormatException usually occurs when you try to do something like convert a String to a numeric value, like an int, float, double, long, etc. NumberFormatException example. The best way to show a NumberFormatException is by example, so here’s an example where I intentionally write bad Java code to throw a

NumberFormatException: Invalid double: "" � Issue #356 , 4.4 App Version: 17 (Lite) User Message: none Stack Trace: java.lang. NumberFormatException: Invalid double: "" at java.lang.StringToReal. java.lang.NumberFormatException: Invalid double: "" Já não sei o que fazer. O erro acontece quando eu deixo um valor em branco, por exemplo, o app faz a soma de 2 números se o usuário digitar apenas um número e clicar em somar o app para e informa que ocorreu um erro, se o usuário digitar o número 1 e o número 2 e depois clicar em somar

Comments
  • "" does not present a double! You must test for empty string before you convert to double.
  • on which line you get this type of error?
  • i got this error at line 52
  • Instead of: double amount = Double.parseDouble(amt.toString()); , I had to do: double amount = new Double(amt.getText().toString());, When retrieving user input. Thanks.
  • This answer doesn't help here, since this exception here is caused by an empty String.
  • Maybe this answer don't solve the question asked here, but for people who search for the same exception, need to know all the possible issues. In my case, this is the valid answer for the same exception and code.