It’s a little old thread, but I recently made excessive performance tests with marshaling in C#. I need to unmarshal lots of data from a serial port over many days. It was important to me to have no memory leaks (because the smallest leak will get significant after a couple of million calls) and I … Read more
unsafe keyword is a marker that you use to tell the compiler that you know what you are doing. Its main purpose is similar to documenting your code: unsafe block shows parts of your code that you designate as unmanaged territory; there is no impact on the actual execution of code. With this in mind, … Read more
There is a nice post about it on mishadoff’s blog here. The class is officially undocumented though.
When is this needed? Under what circumstances does using pointers becomes inevitable? When the net cost of a managed, safe solution is unacceptable but the net cost of an unsafe solution is acceptable. You can determine the net cost or net benefit by subtracting the total benefits from the total costs. The benefits of an … Read more
All objects in Java are references and you can use them like pointers. abstract class Animal {… } class Lion extends Animal {… } class Tiger extends Animal { public Tiger() {…} public void growl(){…} } Tiger first = null; Tiger second = new Tiger(); Tiger third; Dereferencing a null: first.growl(); // ERROR, first is … Read more
To use unsafe code blocks, the project has to be compiled with the /unsafe switch on. Open the properties for the project, go to the Build tab and check the Allow unsafe code checkbox.
examples VM “intrinsification.” ie CAS (Compare-And-Swap) used in Lock-Free Hash Tables eg:sun.misc.Unsafe.compareAndSwapInt it can make real JNI calls into native code that contains special instructions for CAS read more about CAS here http://en.wikipedia.org/wiki/Compare-and-swap The sun.misc.Unsafe functionality of the host VM can be used to allocate uninitialized objects and then interpret the constructor invocation as any … Read more