Principles
The basic principles of garbage collection are:
- Find data objects in a program that cannot be accessed in the future
- Reclaim the resources used by those objects
Many computer languages require garbage collection, either as part of the language specification (e.g., Java, C#, and most scripting languages) or effectively for practical implementation (e.g., formal languages like lambda calculus); these are said to be garbage collected languages. Other languages were designed for use with manual memory management, but have garbage collected implementations available (e.g., C, C++). Some languages, like Ada, Modula-3, and C++/CLI allow both garbage collection and manual memory management to co-exist in the same application by using separate heaps for collected and manually managed objects; others, like D, are garbage collected but allow the user to manually delete objects and also entirely disable garbage collection when speed is required. While integrating garbage collection into the language's compiler and runtime system enables a much wider choice of methods, post hoc GC systems exist, including some that do not require recompilation. (Post-hoc GC is sometimes distinguished as litter collection.) The garbage collector will almost always be closely integrated with the memory allocator.
Read more about this topic: Garbage Collection (computer Science)
Famous quotes containing the word principles:
“Custom is our nature.... What are our natural principles but principles of custom?”
—Blaise Pascal (1623–1662)
“Only conservatives believe that subversion is still being carried on in the arts and that society is being shaken by it.... Advanced art today is no longer a cause—it contains no moral imperative. There is no virtue in clinging to principles and standards, no vice in selling or in selling out.”
—Harold Rosenberg (1906–1978)
“The same principles which at first view lead to skepticism, pursued to a certain point, bring men back to common sense.”
—George Berkeley (1685–1753)