[jdom-interest] Text class (Modified)

[Amy Lewis]

Yah, there was just a suggestion to reuse the string buffer, instead of
making a new one each time the value is set, so:

On Sun, May 27, 2001 at 04:42:12PM -0500, Brett McLaughlin wrote:
>OK. So now we're at:
>
>public class Text {
>
>    private StringBuffer value;

private StringBuffer value = new StringBuffer();

>    private Element parent;
>
>    protected Text() { }
>
>    public Text(String stringValue) {
>        value = new StringBuffer(stringValue);

value.setLength(0);
value.append(stringValue);

>    }
>
>    public String getValue() {
>        return value.toString();
>    }

Since the underlying abstraction is a StringBuffer, is it permissible
to expose that for those who want to be able to use replace() et alii
without creating a new SB then calling setValue?  If so:

    public StringBuffer getBuffer() {
        return value;
    }

The question is: would this cause inflexibility if, in future, some
other implementation were chosen?  It's easy enough, of course, to
return new StringBuffer(getValue()), but that won't work ... if the
semantics are to be that the returned buffer is live (changing it
changes the owning Text).  So it's presented for discussion.

>
>    public void setValue(String stringValue) {
>        value = new StringBuffer(stringValue);

value.setLength(0);
value.append(stringValue);

>    }

You might also want (for ease in copying)

public void setValue(Text other)
{
    value.setLength(0);
    value.append(other.value);
}

(ugh, needs a test for null)

>
>    public void append(String stringValue) {
>        value.append(stringValue);
>    }
>
>    public Element getParent() {
>        return parent;
>    }
>
>    protected void setParent(Element parent) {
>        this.parent = parent;
>    }
>
>    public String toString() {
>        return getValue();
>    }
>
>    public int hashCode() {
>        return value.toString().hashCode();
>    }
>
>    public Object clone() {
>        Text newText = new Text(value);
>        newText.setParent(parent);
>    }
>
>    public boolean equals(Object ob) {
>        if (ob instanceof Text) {
>            if (((Text)ob).value.equals(value)) {
>                return true;
>            }
>        }
>        return false;
>    }

I'd suggest allowing this to be polymorphic, although I'm not quite
certain that this is the best thing to do.  If you did so, then you'd
add: else if (ob instanceof StringBuffer) { ... } else if (ob instanceof
String) { ... }

However, I dunno if this is necessarily the semantics that equals ought
to have.  So consider it for discussion only.

>}

Amy!
-- 
Amelia A. Lewis         alicorn at mindspring.com           amyzing at talsever.com
To be whole is to be part; true voyage is return.
                -- Laia Asieo Odo (Ursula K. LeGuin, "The Dispossessed")