package org.nutz.castor.castor;
import org.nutz.castor.Castor;
import org.nutz.castor.FailToCastObjectException;
import org.nutz.lang.Lang;
import org.nutz.lang.Mirror;
import org.nutz.lang.Strings;
/**
* 根据一个字符串将其转换成 Number 类型。这里有几个规则
* <ul>
* <li>如果 Number 为原生类型，空白串将被转换成 0
* <li>如果 Number 为外覆类，空白串将被转换成 null
* </ul>
*
* 如果转换失败，将抛出 FailToCastObjectException
*
* @author zozoh(zozohtnt@gmail.com)
*/
public class String2Number extends Castor<String, Number> {
@Override
public Number cast(String src, Class<?> toType, String... args) {
if (Strings.isBlank(src)) {
if (toType.isPrimitive())
return 0;
else
return null;
}
if (!toType.isPrimitive() && ("null".equals(src) || "NULL".equals(src) || "Null".equals(src))){
return null;
}
try {
return (Number) Mirror.me(toType)
.getWrapperClass()
.getConstructor(String.class)
.newInstance(src);
}
catch (Exception e) {
throw new FailToCastObjectException(String.format( "Fail to cast '%s' to <%s>",
src,
toType.getName()), Lang.unwrapThrow(e));
}
}
}