Java.lang.Long cannot is cast to Java.lang.Integer solution

Source: Internet
Author: User

Struts and Hibernate integrated pagination display: When the Java.lang.Long cannot is cast to java.lang.Integer problem occurs,

The reasons are:
Here, before Hibernate2.0, version list.get (0) returns an integer type.
However, after Hibernate3.0, version list.get (0) returns a long type.
Therefore, it is not possible to turn the long type into an integer type.

Integers are immutable types, and long and integer do not have any inheritance relationships, and of course cannot convert

For example:
Note: super.pagequery (hql,null,null,null); Invokes a wrapper method for a parent class. Use when querying
List List = This.gethibernatetemplate (). Executefind (New Hibernatecallback () {});

 Public Integer Getuserscount () {      = "SELECT count (*) from Users";       Super NULL NULL NULL );       return (Integer) list.get (0);   }  

Here's the workaround

 Public Integer Getuserscount () {    = "SELECT count (*) from Users";     Super NULL NULL NULL );     = (number) list.get (0);     return Num.intvalue ();    }          

Note: Java.lang.Number is the parent class of Integer,long.

Java.lang.Long cannot is cast to Java.lang.Integer solution

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