81 lines
2.7 KiB
Plaintext
81 lines
2.7 KiB
Plaintext
= Java =
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Java is a strongly typed, garbage collected language that runs in the JVM. It
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can run on almost anything.
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== Data structures ==
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| C++ DS | Java DS | Notes |
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| Vector | ArrayList | Threadsafe |
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| Vector | Vector | Not threadsafe; deprecated |
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| Deque | Deque | |
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| Stack | Stack | Stack implementation using a vector |
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| List | ArrayList | Both linked lists; Singly linked |
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| List | LinkedList | Doubly linked list |
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| Map | TreeMap | Red-black tree |
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| Set | TreeSet | Red-black tree |
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| unordered_set | Hashset | Hashtable |
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| unordered_map | Hashmap | Non blocking but race conditions can occour |
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| unordered_map | Hashtable | Threadsafe but blocking; deprecated |
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| N/A | LinkedHashMap | LRUCache; Hash table that knows order of elements inserted/accessed |
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| N/A | LinkedHashSet | LRUCache; Hash set that knows order of elements inserted/accessed |
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== Primatives ==
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| Name | Size (bits) |
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| byte | 8 |
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| short | 16 |
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| int | 32 |
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| long | 64 |
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| float | 32 |
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| double | 64 |
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| char | 16 |
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| boolean | 1 |
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== Classes ==
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=== Constructor ===
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{{{
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public class MyClass{
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public MyClass(){
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//constructor code here
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}
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}
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}}}
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=== Copy Constructor ===
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{{{
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public class MyClass{
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public MyClass(MyClass myclass){
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//copy constructor here
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}
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}
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}}}
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=== Deconstructor/Finalize ===
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finalize provides security and is called by the garbage collector. We can call
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it directly to clean up the object. All exceptions thrown by it are ignored by
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the garbage collector.
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{{{
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public class MyClass{
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public MyClass(){
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//constructor code here
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}
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protected void finalize(){
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//clean up code here
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}
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}
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}}}
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== Keywords ==
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| C++ | Java | Notes |
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| const | final | Sets a value to be unchangable; aka immutable |
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