The Class instances for the primitive types are obtainable as you said using e.g. int.class, but it is also possible to get the same values using something like Integer.TYPE. Each primitive wrapper class contains a static field, TYPE, which has the corresponding primitive class instance. You cannot obtain the primitive class via forName, but you … Read more
Will this allocate a new memory location? Or just replace the original value? Java does not really make any guarantees that variables will correspond to memory locations; for example, your method might be optimized in such a way that i is stored in a register — or might not even be stored at all, if … Read more
You’re using the wrong constant to check for Long primitives – use Long.TYPE, each other primitive type can be found with a similarly named constant on the wrapper. eg: Byte.TYPE, Character.TYPE, etc.
There is a class for every array type, so there’s a class for int[], there’s a class for Foo[]. These classes are created by JVM. You can access them by int[].class, Foo[].class. The direct super class of these classes are Object.class public static void main(String[] args) { test(int[].class); test(String[].class); } static void test(Class clazz) { … Read more
the Integer class is provided so that values can be boxed/unboxed in a pure OO manner. use int where appropriate unless you specifically need to use it in an OO way; in which case Integer is appropriate. Java Int vs Integer However, very different things are going on under the covers here. An int is … Read more
The >>> operator is the unsigned right bit-shift operator in Java. It effectively divides the operand by 2 to the power of the right operand, or just 2 here. The difference between >> and >>> would only show up when shifting negative numbers. The >> operator shifts a 1 bit into the most significant bit … Read more
Character.getNumericValue(c) The java.lang.Character.getNumericValue(char ch) returns the int value that the specified Unicode character represents. For example, the character ‘\u216C’ (the roman numeral fifty) will return an int with a value of 50. The letters A-Z in their uppercase (‘\u0041’ through ‘\u005A’), lowercase (‘\u0061’ through ‘\u007A’), and full width variant (‘\uFF21’ through ‘\uFF3A’ and ‘\uFF41’ through … Read more
For (non-nullable) object types, Kotlin uses the null value to mark that a lateinit property has not been initialized and to throw the appropriate exception when the property is accessed. For primitive types, there is no such value, so there is no way to mark a property as non-initialized and to provide the diagnostics that … Read more
public class Class1<GenericType> where GenericType : struct { } This one seemed to do the job..
Integer is a better option, as it can handle null; for int, null would become 0, silently, if resultSet.getInt(..) is used. Otherwise, it might throw some exception, something like, “Unable to set null to a primitive property”. Performance is of little concern here. if you choose int, you will end-up adding extra handling code; and … Read more