What is the best practice for java constants class?

I create a constant class by looking at some of the best practices described here in stackoverflow. Many of those have a single Constant class with variables. Some of the answers suggested creating separate Contact Classes. The way I create a constant class is by naming it Parameters and creating classes i.e. Variables and Constants. Then these classes further have child classes e.g. URL, Columns etc. This time I created a constant class with the same structure and a separate class named ReportTemplate. This is my first time creating a Constant class of Objects that don't have a primitive data type.

public final class ReportTemplate {
   public final static class ColumnIds {
        public static final String TITLE_COLUMN_ID = "title";
        public static final String TYPE_COLUMN_ID = "type";
        public static final String LIFECYCLESTATUS_COLUMN_ID = "lifecycle status";
        public static final String INSERTIONTIMESTAMP_COLUMN_ID = "insertionTimestamp";
    }
   public final static class Columns {
        public static final TextColumnBuilder TITLE = col.column(
                "Title", ColumnIds.TITLE, type.stringType());
public static final TextColumnBuilder LIFECYCLESTATUS = col.column(
                "Lifecycle Status", ColumnIds.LIFECYCLESTATUS,
                type.stringType());
        public static final TextColumnBuilder TYPE = col.column("Type",
                ColumnIds.TYPE, type.stringType());
        public static final TextColumnBuilder INSERTIONTIMESTAMP = col
                .column("Insertion Timestamp",
                        ColumnIds.INSERTIONTIMESTAMP,
                        type.stringType());
    }
 public final static class Styles {
        public static final StyleBuilder HEADING1 = style.style()
                .setName("heading 1").bold().setFontSize(15);
        public static final StyleBuilder HEADING2 = stl.style().setName("heading2")
                .bold().setFontSize(12);
        public static final StyleBuilder HEADING3 = style.style().setName("heading3")
                .bold().setFontSize(10);
    }
}

I want to know if my

Naming Scheme is correct Constant class structure is among best practices.

Should I create separate constant classes or have them encapsulated in a parent Constant