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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
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 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package com.sun.beans.decoder;

This class is intended to handle <string> element. This element specifies String values. The result value is created from text of the body of this element. For example:
<string>description</string>
 is equivalent to "description" in Java code. The value of inner element is calculated before adding to the string using String.valueOf(Object). Note that all characters are used including whitespaces (' ', '\t', '\n', '\r'). So the value of the element
<string><true></string>
is not equal to the value of the element
<string>
    <true>
</string>
The following attribute is supported:

id
the identifier of the variable that is intended to store the result

Author:
Sergey A. Malenkov
Since:
1.7/**
 * This class is intended to handle &lt;string&gt; element.
 * This element specifies {@link String} values.
 * The result value is created from text of the body of this element.
 * For example:<pre>
 * &lt;string&gt;description&lt;/string&gt;</pre>
 * is equivalent to {@code "description"} in Java code.
 * The value of inner element is calculated
 * before adding to the string using {@link String#valueOf(Object)}.
 * Note that all characters are used including whitespaces (' ', '\t', '\n', '\r').
 * So the value of the element<pre>
 * &lt;string&gt&lt;true&gt&lt;/string&gt;</pre>
 * is not equal to the value of the element<pre>
 * &lt;string&gt;
 *     &lt;true&gt;
 * &lt;/string&gt;</pre>
 * <p>The following attribute is supported:
 * <dl>
 * <dt>id
 * <dd>the identifier of the variable that is intended to store the result
 * </dl>
 *
 * @since 1.7
 *
 * @author Sergey A. Malenkov
 */
public class StringElementHandler extends ElementHandler {
    private StringBuilder sb = new StringBuilder();
    private ValueObject value = ValueObjectImpl.NULL;

    
Adds the character that contained in this element.
Params:
ch –  the character/**
     * Adds the character that contained in this element.
     *
     * @param ch  the character
     */
    @Override
    public final void addCharacter(char ch) {
        if (this.sb == null) {
            throw new IllegalStateException("Could not add chararcter to evaluated string element");
        }
        this.sb.append(ch);
    }

    
Adds the string value of the argument to the string value of this element.
Params:
argument –  the value of the element that contained in this one/**
     * Adds the string value of the argument to the string value of this element.
     *
     * @param argument  the value of the element that contained in this one
     */
    @Override
    protected final void addArgument(Object argument) {
        if (this.sb == null) {
            throw new IllegalStateException("Could not add argument to evaluated string element");
        }
        this.sb.append(argument);
    }

    
Returns the value of this element.
Returns:
the value of this element/**
     * Returns the value of this element.
     *
     * @return the value of this element
     */
    @Override
    protected final ValueObject getValueObject() {
        if (this.sb != null) {
            try {
                this.value = ValueObjectImpl.create(getValue(this.sb.toString()));
            }
            catch (RuntimeException exception) {
                getOwner().handleException(exception);
            }
            finally {
                this.sb = null;
            }
        }
        return this.value;
    }

    
Returns the text of the body of this element.
This method evaluates value from text of the body,
and should be overridden in those handlers
that extend behavior of this element.
Params:
argument –  the text of the body
Returns:
evaluated value/**
     * Returns the text of the body of this element.
     * This method evaluates value from text of the body,
     * and should be overridden in those handlers
     * that extend behavior of this element.
     *
     * @param argument  the text of the body
     * @return evaluated value
     */
    protected Object getValue(String argument) {
        return argument;
    }
}