Is it possible to assign numeric value to an enum in Java

Question

Is anything like this possible in Java  Can one assign custom numeric values to enum elements in Java   public enum EXIT CODE       A 104  B 203

User · Answer

Extending Bhesh Gurung s answer for assigning values  you can add explicit method to set value     public ExitCode setValue  int value             A 104   B 203         switch value           case 104  return ExitCode A          case 203  return ExitCode B          default                     return ExitCode Unknown   Keep an default or error enum handy                From calling application  int i   104   ExitCode serverExitCode   ExitCode setValue i       You ve valid enum from now   Unable to comment to his answer  hence posting it separately

User · Answer

public enum EXIT CODE       A 104   B 203        private int numVal       EXIT CODE int numVal            this numVal   numVal             public int getNumVal             return numVal

User · Answer

Assuming that EXIT CODE is referring to System   exit   exit code   then you could do  enum ExitCode         NORMAL SHUTDOWN   0     EMERGENCY SHUTDOWN   10     OUT OF MEMORY   20     WHATEVER   30            private int value          ExitCode   int value                      this   value   value                  public void exit                         System   exit   value                 Then you can put the following at appropriate spots in your code  ExitCode   NORMAL SHUTDOWN   exit

User · Answer

I realize this is an older question  but it comes up first in a Google search  and among the excellent answers provided  I didn t see anything fully comprehensive  so I did a little more digging and I ended up writing an enum class that not only allowed me to assign multiple custom values to the enum constants  I even added a method that allows me to assign values to them on the fly during code execution  This enum class is for a  quot server quot  program that I run on a Raspberry Pi  The program receives commands from a client then it executes terminal commands that make adjustments to a webcam that is affixed to my 3D printer  Using the Linux program  v4l2-ctl  on the Pi  you can extract all of the possible adjustment commands for a given attached webcam  which also provides the setting datatype  the min and max values  the number of value steps in a given value range etc   so I took all of those and put them in an enum and created an enum interface that makes it easy to both set and get values for each command as well as a simple method to get the actual terminal command that is executed  using the Process and Runtime classes  in order to adjust the setting  It is a rather large class and I apologize for that  but for me  it s always easier to learn something when I can see it working in full context  so I decided not to scale it down  However  even though it s large  it is definitely simple and it should be obvious what s happening in the class with minimal effort  package constants   import java util HashMap  import java util Map   public enum PICam       BRIGHTNESS                    quot brightness quot                    0        quot int quot        0       100     1   50       CONTRAST                      quot contrast quot                      1        quot int quot        100     100     1   0       SATURATION                    quot saturation quot                    2        quot int quot        100     100     1   0       RED BALANCE                   quot red balance quot                   3        quot intmenu quot    1       7999    1   1000       BLUE BALANCE                  quot blue balance quot                  4        quot int quot        1       7999    1   1000       HORIZONTAL FLIP               quot horizontal flip quot               5        quot bool quot       0       1       1   0       VERTICAL FLIP                 quot vertical flip quot                 6        quot bool quot       0       1       1   0       POWER LINE FREQUENCY          quot power line frequency quot          7        quot menu quot       0       3       1   1       SHARPNESS                     quot sharpness quot                     8        quot int quot        100     100     1   0       COLOR EFFECTS                 quot color effects quot                 9        quot menu quot       0       15      1   0       ROTATE                        quot rotate quot                        10       quot int quot        0       360     90  0       COLOR EFFECTS CBCR            quot color effects cbcr quot            11       quot int quot        0       65535   1   32896       VIDEO BITRATE MODE            quot video bitrate mode quot            12       quot menu quot       0       1       1   0       VIDEO BITRATE                 quot video bitrate quot                 13       quot int quot        25000   25000000    25000   10000000       REPEAT SEQUENCE HEADER        quot repeat sequence header quot        14       quot bool quot       0       1       1   0       H264 I FRAME PERIOD           quot h 264 i frame period quot          15       quot int quot        0       2147483647 1    60       H264 LEVEL                    quot h 264 level quot                   16       quot menu quot       0       11      1   11       H264 PROFILE                  quot h 264 profile quot                 17       quot menu quot       0       4       1   4       AUTO EXPOSURE                 quot auto exposure quot                 18       quot menu quot       0       3       1   0       EXPOSURE TIME ABSOLUTE        quot exposure time absolute quot        19       quot int quot        1       10000   1   1000       EXPOSURE DYNAMIC FRAMERATE    quot exposure dynamic framerate quot    20       quot bool quot       0       1       1   0       AUTO EXPOSURE BIAS            quot auto exposure bias quot            21       quot intmenu quot    0       24      1   12       WHITE BALANCE AUTO PRESET     quot white balance auto preset quot     22       quot menu quot       0       9       1   1       IMAGE STABILIZATION           quot image stabilization quot           23       quot bool quot       0       1       1   0       ISO SENSITIVITY               quot iso sensitivity quot               24       quot intmenu quot    0       4       1   0       ISO SENSITIVITY AUTO          quot iso sensitivity auto quot          25       quot menu quot       0       1       1   1       EXPOSURE METERING MODE        quot exposure metering mode quot        26       quot menu quot       0       2       1   0       SCENE MODE                    quot scene mode quot                    27       quot menu quot       0       13      1   0       COMPRESSION QUALITY           quot compression quality quot           28       quot int quot        1       100     1   30         private static final Map lt String  PICam gt     LABEL MAP         new HashMap lt  gt         private static final Map lt Integer  PICam gt    INDEX MAP         new HashMap lt  gt         private static final Map lt String  PICam gt     TYPE MAP          new HashMap lt  gt         private static final Map lt Integer  PICam gt    MIN MAP           new HashMap lt  gt         private static final Map lt Integer  PICam gt    MAX MAP           new HashMap lt  gt         private static final Map lt Integer  PICam gt    STEP MAP          new HashMap lt  gt         private static final Map lt Integer  PICam gt    DEFAULT MAP       new HashMap lt  gt         private static final Map lt Integer  Integer gt  THIS VALUE MAP    new HashMap lt  gt          private static final String                baseCommandLine    quot  usr bin v4l2-ctl -d  dev video0 --set-ctrl  quot        static           for  PICam e  values                  LABEL MAP put e label  e               INDEX MAP put e index  e               TYPE MAP put e type  e               MIN MAP put e min  e               MAX MAP put e max  e               STEP MAP put e step  e               DEFAULT MAP put e defaultValue  e                        public final String label      public final int index      public final String type      public final int min      public final int max      public final int step      public final int defaultValue       private PICam String label  int index  String type  int min  int max  int step  int defaultValue            this label   label          this index   index          this type   type          this min   min          this max   max          this step   step          this defaultValue   defaultValue             public static void setValue Integer index  Integer value            if  THIS VALUE MAP containsKey index   THIS VALUE MAP replace index  value           else THIS VALUE MAP put index  value              public Integer getValue  Integer index            return THIS VALUE MAP getOrDefault index  null              public static PICam getLabel String label            return LABEL MAP get label              public static PICam getType String type            return TYPE MAP get type              public static PICam getMin int min            return MIN MAP get min              public static PICam getMax int max            return MAX MAP get max              public static PICam getStep int step            return STEP MAP get step              public static PICam getDefault int defaultValue            return DEFAULT MAP get defaultValue              public static String getCommandFor int index  int newValue            PICam picam   INDEX MAP get index           String commandValue    quot  quot           if   quot bool quot  equals picam type                 commandValue    newValue    0     quot false quot     quot true quot                     else               commandValue   String valueOf newValue                     return baseCommandLine   INDEX MAP get index  label    quot   quot    commandValue             public static String getCommandFor PICam picam  Integer newValue            String commandValue    quot  quot           if   quot bool quot  equals picam type                 commandValue    newValue    0     quot false quot     quot true quot                     else               commandValue   String valueOf newValue                     return baseCommandLine   INDEX MAP get picam index  label    quot   quot    commandValue             public static String getCommandFor PICam piCam            int    newValue       piCam defaultValue          String commandValue    quot  quot           if   quot bool quot  equals piCam type                 commandValue    newValue    0     quot false quot     quot true quot                     else               commandValue   String valueOf newValue                     return baseCommandLine   piCam label    quot   quot    commandValue             public static String getCommandFor Integer index            PICam piCam   INDEX MAP get index           int    newValue       piCam defaultValue          String commandValue    quot  quot           if   quot bool quot  equals piCam type                 commandValue    newValue    0     quot false quot     quot true quot                     else               commandValue   String valueOf newValue                     return baseCommandLine   piCam label    quot   quot    commandValue           Here are some ways that the class can be interacted with  This code  public static void test         PICam setValue 0 127     Set brightness to 125     PICam setValue PICam SHARPNESS 143     Set sharpness to 125     String command1   PICam getSetCommandStringFor PICam BRIGHTNESS     Get command line string to include the brightness value that we previously set referencing it by enum constant      String command2   PICam getSetCommandStringFor 0     Get command line string to include the brightness value that we previously set referencing it by index number      String command3   PICam getDefaultCamString PICam BRIGHTNESS     Get command line string with the default value     String command4   PICam getSetCommandStringFor PICam SHARPNESS     Get command line string with the sharpness value that we previously set      String command5   PICam getDefaultCamString PICam SHARPNESS     Get command line string with the default sharpness value      System out println command1       System out println command2       System out println command3       System out println command4       System out println command5      Produces these results   usr bin v4l2-ctl -d  dev video0 --set-ctrl brightness 127  usr bin v4l2-ctl -d  dev video0 --set-ctrl brightness 127  usr bin v4l2-ctl -d  dev video0 --set-ctrl brightness 50  usr bin v4l2-ctl -d  dev video0 --set-ctrl sharpness 143  usr bin v4l2-ctl -d  dev video0 --set-ctrl sharpness 0

User · Answer

Yes  and then some  example from documentation   public enum Planet       MERCURY  3 303e 23  2 4397e6       VENUS    4 869e 24  6 0518e6       EARTH    5 976e 24  6 37814e6       MARS     6 421e 23  3 3972e6       JUPITER  1 9e 27    7 1492e7       SATURN   5 688e 26  6 0268e7       URANUS   8 686e 25  2 5559e7       NEPTUNE  1 024e 26  2 4746e7           in kilograms     private final double mass         in meters     private final double radius      Planet double mass  double radius            this mass   mass          this radius   radius            private double mass     return mass        private double radius     return radius            universal gravitational         constant   m3 kg-1 s-2      public static final double G   6 67300E-11       double surfaceGravity             return G   mass    radius   radius             double surfaceWeight double otherMass            return otherMass   surfaceGravity              public static void main String   args            if  args length    1                System err println  Usage  java Planet  lt earth weight gt                 System exit -1                     double earthWeight   Double parseDouble args 0            double mass   earthWeight EARTH surfaceGravity            for  Planet p   Planet values               System out printf  Your weight on  s is  f n                                p  p surfaceWeight mass

User · Answer

If you re looking for a way to group constants in a class  you can use a static inner class   public class OuterClass       public void exit boolean isTrue           if isTrue               System exit ExitCode A            else              System exit ExitCode B                       public static class ExitCode          public static final int A   203          public static final int B   204

[java] Is it possible to assign numeric value to an enum in Java?

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