jetbrick.web.mvc.action.annotations.RequestParamArgumentGetter Maven / Gradle / Ivy
/**
* Copyright 2013-2014 Guoqiang Chen, Shanghai, China. All rights reserved.
*
* Email: [email protected]
* URL: http://subchen.github.io/
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package jetbrick.web.mvc.action.annotations;
import jetbrick.ioc.annotations.Managed;
import jetbrick.lang.ArrayUtils;
import jetbrick.lang.StringUtils;
import jetbrick.lang.annotations.ValueConstants;
import jetbrick.typecast.Convertor;
import jetbrick.typecast.TypeCastUtils;
import jetbrick.web.mvc.RequestContext;
import jetbrick.web.mvc.multipart.FilePart;
@Managed
public class RequestParamArgumentGetter implements AnnotatedArgumentGetter {
// 区分不同的场景
private enum Scenario {
FILE, ARRAY, ELEMENT
}
private Scenario scenario;
private Class type; // 参数类型
private String name;
private boolean required;
private String defaultValue;
private Convertor cast;
@Override
public void initialize(ArgumentContext ctx) {
type = ctx.getRawParameterType();
if (FilePart.class.isAssignableFrom(type)) {
scenario = Scenario.FILE;
cast = null;
} else if (type.isArray()) {
scenario = Scenario.ARRAY;
type = type.getComponentType();
cast = null;
} else {
scenario = Scenario.ELEMENT;
cast = ctx.getTypeConvertor();
}
RequestParam annotation = ctx.getAnnotation();
name = annotation.value();
if (ValueConstants.isEmptyOrNull(name)) {
name = ctx.getParameterName();
}
required = annotation.required();
defaultValue = ValueConstants.trimToNull(annotation.defaultValue());
}
@Override
public Object get(RequestContext ctx) {
switch (scenario) {
case ELEMENT: {
String value = ctx.getParameter(name);
if (value == null) {
value = defaultValue;
}
if (value == null) {
if (required) {
throw new IllegalStateException("request parameter is not found: " + name);
}
return null;
}
if (cast != null) {
return cast.convert(value);
}
return value;
}
case ARRAY: {
String[] values = ctx.getParameterValues(name);
if (values == null) {
if (defaultValue != null) {
values = StringUtils.split(defaultValue, ',');
}
}
if (values == null) {
values = ArrayUtils.EMPTY_STRING_ARRAY;
}
return TypeCastUtils.convertToArray(values, type);
}
case FILE: {
Object value = ctx.getFilePart(name);
if (value == null && required) {
throw new IllegalStateException("upload file object is not found: " + name);
}
return value;
}
}
throw new IllegalStateException("unreachable");
}
}