View Javadoc

    1   /*
    2    * Licensed to the Apache Software Foundation (ASF) under one or more
    3    * contributor license agreements.  See the NOTICE file distributed with
    4    * this work for additional information regarding copyright ownership.
    5    * The ASF licenses this file to You under the Apache License, Version 2.0
    6    * (the "License"); you may not use this file except in compliance with
    7    * the License.  You may obtain a copy of the License at
    8    *
    9    *      http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   */
    17  package org.apache.mina.integration.ognl;
    18
    19  import java.beans.PropertyEditor;
    20  import java.lang.reflect.Member;
    21  import java.util.Map;
    22
    23  import ognl.OgnlContext;
    24  import ognl.TypeConverter;
    25
    26  import org.apache.mina.integration.beans.PropertyEditorFactory;
    27
    28  /**
    29   * {@link PropertyEditor}-based implementation of OGNL {@link TypeConverter}.
    30   * This converter uses the {@link PropertyEditor} implementations in
    31   * <tt>mina-integration-beans</tt> module to perform conversion.  To use this
    32   * converter:
    33   * <pre><code>
    34   * OgnlContext ctx = Ognl.createDefaultContext(root);
    35   * ctx.put(OgnlContext.TYPE_CONVERTER_CONTEXT_KEY, new PropertyTypeConverter());
    36   * </code></pre>
    37   * You can also override {@link #getPropertyEditor(Class, String, Class)}
    38   * method to have more control over how an appropriate {@link PropertyEditor}
    39   * is chosen.
    40   *
    41   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
    42   */
    43  public class PropertyTypeConverter implements TypeConverter {
    44
    45      @SuppressWarnings("unchecked")
    46      public Object convertValue(Map ctx, Object target, Member member, String attrName, Object value, Class toType) {
    47          if (value == null) {
    48              return null;
    49          }
    50
    51          if (attrName == null) {
    52              // I don't know why but OGNL gives null attrName almost always.
    53              // Fortunately, we can get the actual attrName with a tiny hack.
    54              OgnlContext ognlCtx = (OgnlContext) ctx;
    55              attrName = ognlCtx.getCurrentNode().toString().replaceAll("[\" \']+", "");
    56          }
    57
    58          if (toType.isAssignableFrom(value.getClass())) {
    59              return value;
    60          }
    61
    62          PropertyEditor e1 = getPropertyEditor(target.getClass(), attrName, value.getClass());
    63          if (e1 == null) {
    64              throw new IllegalArgumentException("Can't convert " + value.getClass().getSimpleName() + " to "
    65                      + String.class.getSimpleName());
    66          }
    67          e1.setValue(value);
    68
    69          PropertyEditor e2 = getPropertyEditor(target.getClass(), attrName, toType);
    70          if (e2 == null) {
    71              throw new IllegalArgumentException("Can't convert " + String.class.getSimpleName() + " to "
    72                      + toType.getSimpleName());
    73          }
    74
    75          e2.setAsText(e1.getAsText());
    76          return e2.getValue();
    77      }
    78
    79      protected PropertyEditor getPropertyEditor(Class<?> type, String attrName, Class<?> attrType) {
    80          return PropertyEditorFactory.getInstance(attrType);
    81      }
    82  }