NumberFormatException：对于输入字符串：“5,2”

Question

Please help me with this issue. I am adding code snippet and crash log here.

Code:

if (rssi <= -30 && rssi >= -90) {
    double len = ((rssi + 20) * -1) / 10.0;
    DecimalFormat decimalFormat = new DecimalFormat("#.##");
    float twoDigitsF = Float.valueOf(decimalFormat.format(len));
    return String.valueOf(twoDigitsF);
}

I am getting the exception at the line

float twoDigitsF = Float.valueOf(decimalFormat.format(len));

Here I am attaching my logs

Fatal Exception: java.lang.NumberFormatException: For input string: "5,2"
       at java.lang.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1306)
       at java.lang.Float.valueOf(Float.java:424)
       at com.app.package.utils.Util.getRange(Util.java:26)
       at com.app.package.DriverActivity.scanDone(SampleActivity.java:982)
       at com.app.package.DriverActivity.access$1300(SampleActivity.java:126)
       at com.app.package.DriverActivity$11.onScanned(SampleActivity.java:913)
       at com.appchannel.bluetooth.BHelper$1.run(BHelper.java:67)
       at android.os.Handler.handleCallback(Handler.java:751)
       at android.os.Handler.dispatchMessage(Handler.java:95)
       at android.os.Looper.loop(Looper.java:154)
       at android.app.ActivityThread.main(ActivityThread.java:6317)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:872)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:762)

I got this log from Crashlytics. I am not able to reproduce this issue on my device.

Answer 1

Depending on what your locale is set to, the character between the integral part and the fractional part of the decimal number can be either . , , , or something else that I'm not aware of.

DecimalFormat automatically uses the character that corresponds to your locale, so that's why it formats to things like 5,2 instead of 5.2 .

However, valueOf does not take locales into account. It looks for . as the separator. So by putting 5,2 in there, valueOf` can't recognise it.

To force the decimal format to format so that the result is compatible with valueOf , try to create the DecimalFormat with this:

new DecimalFormat("#.##", DecimalFormatSymbols.getInstance(Locale.US));

EDIT:

I saw that you convert the float back to a string again and return it. Why don't you just return the return value of format ?

return decimalFormat.format(len);

Answer 2

5,2is not double or float value ,so you should filter error value ! tosetting textview inputtype !

Answer 3

no need to use decimal format.

yourfloat*=100f;
yourfloat = Math.round(yourfloat);
yourfloat =  yourfloat/100f;