- \n
- It makes java memory-efficient because garbage collector removes the unreferenced objects from heap memory.<\/li>\n
- It is automatically done by the garbage collector(a part of JVM) so we don’t need to make extra efforts.<\/li>\n<\/ul>\n
Terms<\/h2>\n
Unreachable objects<\/strong>: An object is said to be unreachable if it doesn\u2019t contain any reference to it.<\/p>\n
Integer i = new Integer(4);
\n\/\/ the new Integer object is reachable via the reference in ‘i’
\ni = null;
\n\/\/ the Integer object is no longer reachable.<\/p>\nEligibility for garbage collection<\/strong> :
\nAn object is said to be eligible for GC(garbage collection) if it is unreachable.<\/p>\nSteps Of Garbage Collection<\/strong><\/p>\n
- \n
- Marking<\/li>\n
- Normal Delation<\/li>\n
- Delation With Compacting<\/li>\n<\/ul>\n
Marking<\/strong><\/p>\n
The garbage collector determines which pieces of memory are in use and which are not.<\/p>\n
<\/p>\n
Normal Delation<\/strong><\/p>\n
Garbage collector removes unreferenced objects leaving referenced objects and pointers to free space.<\/p>\n
<\/p>\n
Delation With Compacting<\/strong><\/p>\n
Garbage collector deletes unreferenced objects and compacts the remaining referenced objects.<\/p>\n
<\/p>\n
![\"Garbage](\"https:\/\/bcisnotes.com\/secondsemester\/wp-content\/uploads\/2019\/08\/java-garbage-collection-scenario.jpg\")
<\/p>\nUnreferenced<\/h2>\n
How can an object be unreferenced?
\nThere are many ways:
\n– By nulling the reference
\n– By assigning a reference to another
\n– By anonymous object etc.<\/p>\nNulling<\/strong><\/p>\n
By nulling a reference:<\/p>\n
Employee\u00a0e=new\u00a0Employee();
\ne=null;<\/p>\nAssigning<\/strong><\/p>\n
By assigning a reference to another:<\/p>\n
Employee\u00a0e1=new\u00a0Employee();
\nEmployee\u00a0e2=new\u00a0Employee();
\ne1=e2;<\/p>\n\/\/now\u00a0the\u00a0first\u00a0object\u00a0referred\u00a0by\u00a0e1\u00a0is\u00a0available\u00a0for\u00a0garbage\u00a0collection<\/p>\n
Anonymous<\/strong><\/p>\n
By anonymous object:<\/p>\n
new\u00a0Employee();<\/p>\n
Final<\/h2>\n
The final keyword in java is used to restrict the user. The java final keyword can be used in many contexts. Final can be:<\/p>\n
- \n
- variable<\/li>\n
- methoD<\/li>\n
- class<\/li>\n<\/ul>\n
Example<\/strong>:<\/p>\n
class\u00a0Bike9{
\nfinal\u00a0int\u00a0speedlimit=90;\/\/final\u00a0variable
\nvoid\u00a0run(){
\nspeedlimit=400;
\n}
\npublic\u00a0static\u00a0void\u00a0main(String\u00a0args[]){
\nBike9\u00a0obj=new\u00a0\u00a0Bike9();
\nobj.run();
\n}
\n}\/\/end\u00a0of\u00a0class<\/p>\nYou may also like Operator Precedence || Java Programming Basics || Bcis Notes<\/a><\/p>\n
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