Java – how do I map values to enumerations?

Given an enumeration, each instance is associated with some values:

public enum sqlState
{
  SUCCESSFUL_COMPLETION("00000"),WARNING("01000");

  private final String code;
  sqlState(String code)
  {
    this.code = code;
  }
}

How to build an effective reverse lookup map? I have tried the following:

public enum sqlState
{
  SUCCESSFUL_COMPLETION("00000"),WARNING("01000");

  private final String code;
  private static final Map<String,sqlState> codeToValue = Maps.newHashMap();
  sqlState(String code)
  {
    this.code = code;
    codeToValue.put(code,this); // problematic line
  }
}

But Java complains that it illegally references static fields from the initializer That is, a static map is initialized after all enumerated values, so you cannot reference it from the constructor Any ideas?

Solution

use:

static {
  for (sqlState sqlState : values()){
     codeToValue.put(sqlState.code,sqlState);
  }
}