When do Enum instances get created?

Question

I have a simple question regarding Enums in Java Please refer to the following code . When do the instances like PropName .CONTENTS get instantiated ?

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;
  }
}

It's created when the class is loaded. But why this question ? What's the problem you have ? — Denys Séguret, Sep 28 '12 at 11:22

score 11 · Accepted Answer · answered Sep 28 '12 at 11:21

11

It's created when the class is loaded, just like any static code block.

answered Sep 28 '12 at 11:21

Denys Séguret

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score 5 · Answer 2 · answered Sep 28 '12 at 11:22

5

When the PropName class is loaded by the class loader. Enum constants are static final fields of their class.

answered Sep 28 '12 at 11:22

JB Nizet

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How can we see a class being loaded in a debugger ? – MasterJoe Sep 24 '18 at 23:25

Toni Nagy · Answer 3 · 2021-03-24T13:09:29.200

3

The enum types' instances get created in the class loader subsystem in the last phase of "loading the class file", called Initialization and not at runtime, like other class instances. They come first, before any other static field/variable initializations and that is why you can't access static fields inside an enum's constructor either, unless they are a constant.

edited Mar 24 '21 at 13:09

answered Feb 28 '20 at 14:30

Toni Nagy

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When do Enum instances get created?

3 Answers3

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