MONGODB（四）——DBObject与JavaBean转换

一、DBObject 转为 JavaBean

/**
* 将实体Bean对象转换成DBObject
*
*/
public static <T> DBObject beanToDBObject(T bean)
throws IllegalArgumentException, IllegalAccessException {
if (bean == null)
return null;
DBObject dbObject = new BasicDBObject();
// 获取对象类的属性域
Field[] fields = bean.getClass().getDeclaredFields();
for (Field field : fields) {
// 获取变量的属性名
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;
}

二、 JavaBean转为DBObject

/**
* 将DBObject转换成Bean对象
*
*/
public static <T> T dbObjectToBean(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;
}

// 取出Mongo中的属性值，为bean赋值
public static <T> void setProperty(T bean, String varName, T object) {
varName = varName.substring(0, 1).toUpperCase() + varName.substring(1);
try {
String type = object.getClass().getName();
// 类型为String
if (type.equals("java.lang.String")) {
Method m = bean.getClass().getMethod("get" + varName);
String value = (String) m.invoke(bean);
if (value == null) {
m = bean.getClass()
.getMethod("set" + varName, String.class);
m.invoke(bean, object);
}
}
// 类型为Integer
if (type.equals("java.lang.Integer")) {
Method m = bean.getClass().getMethod("get" + varName);
String value = (String) m.invoke(bean);
if (value == null) {
m = bean.getClass().getMethod("set" + varName,
Integer.class);
m.invoke(bean, object);
}
}
// 类型为Boolean
if (type.equals("java.lang.Boolean")) {
Method m = bean.getClass().getMethod("get" + varName);
String value = (String) m.invoke(bean);
if (value == null) {
m = bean.getClass().getMethod("set" + varName,
Boolean.class);
m.invoke(bean, object);
}
}
} catch (NoSuchMethodException e) {
e.printStackTrace();
} catch (SecurityException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
}