java操作mongodb时,对象bean和DBObject相互转换的方法(推荐)

package com.iqbon.spider.util;  import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.util.Date;  import org.apache.commons.beanutils.BeanUtils;  import com.mongodb.BasicDBObject; import com.mongodb.DBObject;  public class BeanUtil {   /**   * 把实体bean对象转换成DBObject   * @param bean   * @return   * @throws IllegalArgumentException   * @throws IllegalAccessException   */  public static <T> DBObject bean2DBObject(T bean) throws IllegalArgumentException,    IllegalAccessException {   if (bean == null) {    return null;   }   DBObject dbObject = new BasicDBObject();   // 获取对象对应类中的所有属性域   Field[] fields = bean.getClass().getDeclaredFields();   for (Field field : fields) {    // 获取属性名    String varName = field.getName();    // 修改访问控制权限    boolean accessFlag = field.isAccessible();    if (!accessFlag) {     field.setAccessible(true);    }    Object param = field.get(bean);    if (param == null) {     continue;    } else if (param instanceof Integer) {//判断变量的类型     int value = ((Integer) param).intValue();     dbObject.put(varName, value);    } else if (param instanceof String) {     String value = (String) param;     dbObject.put(varName, value);    } else if (param instanceof Double) {     double value = ((Double) param).doubleValue();     dbObject.put(varName, value);    } else if (param instanceof Float) {     float value = ((Float) param).floatValue();     dbObject.put(varName, value);    } else if (param instanceof Long) {     long value = ((Long) param).longValue();     dbObject.put(varName, value);    } else if (param instanceof Boolean) {     boolean value = ((Boolean) param).booleanValue();     dbObject.put(varName, value);    } else if (param instanceof Date) {     Date value = (Date) param;     dbObject.put(varName, value);    }    // 恢复访问控制权限    field.setAccessible(accessFlag);   }   return dbObject;  }   /**   * 把DBObject转换成bean对象   * @param dbObject   * @param bean   * @return   * @throws IllegalAccessException   * @throws InvocationTargetException   * @throws NoSuchMethodException   */  public static <T> T dbObject2Bean(DBObject dbObject, T bean) throws IllegalAccessException,    InvocationTargetException, NoSuchMethodException {   if (bean == null) {    return null;   }   Field[] fields = bean.getClass().getDeclaredFields();   for (Field field : fields) {    String varName = field.getName();    Object object = dbObject.get(varName);    if (object != null) {     BeanUtils.setProperty(bean, varName, object);    }   }   return bean;  } }