浅谈java中定义泛型类和定义泛型方法的写法
时间:2021-06-04 07:53:13|栏目:JAVA代码|点击: 次
1、方法中的泛型
public static <T> T backSerializable(Class<T> clazz , String path ,String fileName){
FileInputStream fis = null;
ObjectInputStream ois = null;
Object obj = null;
try {
fis = new FileInputStream(path + fileName);
ois = new ObjectInputStream(fis);
obj = ois.readObject();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
try {
if( fis!=null) fis.close();
if( ois!=null) ois.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return (T)obj;
}
2、定义泛型类
public class PageHibernateCallback<T> implements HibernateCallback<List<T>>{
private String hql;
private Object[] params;
private int startIndex;
private int pageSize;
public PageHibernateCallback(String hql, Object[] params,
int startIndex, int pageSize) {
super();
this.hql = hql;
this.params = params;
this.startIndex = startIndex;
this.pageSize = pageSize;
}
public List<T> doInHibernate(Session session) throws HibernateException,
SQLException {
//1 执行hql语句
Query query = session.createQuery(hql);
//2 实际参数
if(params != null){
for(int i = 0 ; i < params.length ; i ++){
query.setParameter(i, params[i]);
}
}
//3 分页
query.setFirstResult(startIndex);
query.setMaxResults(pageSize);
return query.list();
}
}


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