内容或简介：
/**
调用数据库里的一个函数
一个函数本质上一个返回一个结果的存储过程，这个例子示范了怎么调用有in、out和in/out参数的函数
***********************************/
CallableStatement cs;
try {
// 调用一个没有参数的函数; 函数返回 a VARCHAR
// 预处理callable语句 
    cs = connection.prepareCall("{? = call myfunc}");

// 注册返回值类型
    cs.registerOutParameter(1, i);

// Execute and retrieve the returned value
    cs.execute();
    String retValue = cs.getString(1);

// 调用有一个in参数的函数; the function returns a VARCHAR
    cs = connection.prepareCall("{? = call myfuncin(?)}");

// Register the type of the return value
    cs.registerOutParameter(1, Types.VARCHAR);

// Set the value for the IN parameter
    cs.setString(2, "a string");

// Execute and retrieve the returned value
    cs.execute();
    retValue = cs.getString(1);

// 调用有一个out参数的函数; the function returns a VARCHAR
    cs = connection.prepareCall("{? = call myfuncout(?)}");

// Register the types of the return value and OUT parameter
    cs.registerOutParameter(1, Types.VARCHAR);
    cs.registerOutParameter(2, Types.VARCHAR);

// Execute and retrieve the returned values
    cs.execute();
    retValue = cs.getString(1);           // return value
    String outParam = cs.getString(2);    // OUT parameter

// 调用有一个in/out参数的函数; the function returns a VARCHAR
    cs = connection.prepareCall("{? = call myfuncinout(?)}");

// Register the types of the return value and OUT parameter
    cs.registerOutParameter(1, Types.VARCHAR);
    cs.registerOutParameter(2, Types.VARCHAR);

// Set the value for the IN/OUT parameter
    cs.setString(2, "a string");

// Execute and retrieve the returned values
    cs.execute();
    retValue = cs.getString(1);           // return value
    outParam = cs.getString(2);           // IN/OUT parameter
} catch (SQLException e) {
}