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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 * accompanied this code).

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package com.sun.tools.internal.xjc.generator.util;

import com.sun.codemodel.internal.JCodeModel;

import com.sun.codemodel.internal.JExpr;

import com.sun.codemodel.internal.JExpression;

import com.sun.codemodel.internal.JStringLiteral;

import com.sun.xml.internal.bind.WhiteSpaceProcessor;

/**

 * Generates code that performs the whitespace normalization.

 */

public abstract class WhitespaceNormalizer

{

    /**

     * Generates the expression that normalizes

     * the given expression (which evaluates to java.lang.String).

     *

     * @param codeModel

     *      The owner code model object under which a new expression

     *      will be created.

     */

    public abstract JExpression generate( JCodeModel codeModel, JExpression literal );

    /**

     * Parses "preserve","replace" or "collapse" into

     * the corresponding WhitespaceNormalizer object.

     *

     * @param method

     *      Either "preserve", "replace", or "collapse"

     *

     * @exception    IllegalArgumentException

     *        when the specified method is invalid.

     */

    public static WhitespaceNormalizer parse( String method ) {

        if( method.equals("preserve") )

            return PRESERVE;

        if( method.equals("replace") )

            return REPLACE;

        if( method.equals("collapse") )

            return COLLAPSE;

        throw new IllegalArgumentException(method);

    }

    public static final WhitespaceNormalizer PRESERVE = new WhitespaceNormalizer() {

        public JExpression generate( JCodeModel codeModel, JExpression literal ) {

            return literal;

        }

    };

    public static final WhitespaceNormalizer REPLACE = new WhitespaceNormalizer() {

        public JExpression generate( JCodeModel codeModel, JExpression literal ) {

            // WhitespaceProcessor.replace(<literal>);

            if( literal instanceof JStringLiteral )

                // optimize

                return JExpr.lit( WhiteSpaceProcessor.replace(((JStringLiteral)literal).str) );

            else

                return codeModel.ref(WhiteSpaceProcessor.class)

                    .staticInvoke("replace").arg(literal);

        }

    };

    public static final WhitespaceNormalizer COLLAPSE = new WhitespaceNormalizer() {

        public JExpression generate( JCodeModel codeModel, JExpression literal ) {

            // WhitespaceProcessor.replace(<literal>);

            if( literal instanceof JStringLiteral )

                // optimize

                return JExpr.lit( WhiteSpaceProcessor.collapse(((JStringLiteral)literal).str) );

            else

                return codeModel.ref(WhiteSpaceProcessor.class)

                    .staticInvoke("collapse").arg(literal);

        }

    };

}