This question is basically an extension of my previous question . I asked the previous question to be sure that the Enum constants are populated when the class loads . Here's is my class again with the addition of a simple method getByName
:
public enum PropName {
CONTENTS("contents"),
USE_QUOTES("useQuotes"),
ONKEYDOWN("onkeydown"),
BROWSER_ENTIRE_TABLE("browseEntireTable"),
COLUMN_HEADINGS("columnHeadings"),
PAGE_SIZE("pageSize"),
POPUP_TITLE("popupTitle"),
FILTER_COL("filterCol"),
SQL_SELECT("sqlSelect"),
;
private String name;
private PropName(String name) {
this.name = name;
}
public String getName() {
return name;
}
public static PropName getByName(String name){
return PropName.valueOf(name);
}
}
A call to the method getByName("columnHeadings")
is throwing java.lang.IllegalArgumentException: No enum const class labware.web.component.limsgrid.PropName.columnHeadings
but if I replace this method with the following code it just works .
public static PropName getByName(String name){
for(PropName prop : values()){
if(prop.getName().equals(name)){
return prop;
}
}
throw new IllegalArgumentException(name + " is not a valid PropName");
}
Any ideas as to what I am doing wrong here ?
Enum.valueOf()
only checks the constant name, so you need to pass it "COLUMN_HEADINGS"
instead of "columnHeadings". Your name
property has nothing to do with Enum internals.
To address the questions/concerns in the comments:
The enum's "builtin" (implicitly declared) valueOf(String name)
method will look up an enum constant with that exact name. If your input is "columnHeadings", you have (at least) three choices:
enum PropName { contents, columnHeadings, ...}
. This is obviously the most convenient.valueOf
, if you're really fond of naming conventions.valueOf
to find the corresponding constant for an input. This makes most sense if there are multiple possible mappings for the same set of constants.