Java Random (i)

Jdk>jre>jvm

IDE Integrated development Environment
Configure environment variables path:; C:\Program Files\java\jdk1.6.0_13\bin

1:javac Hello.java compile to generate bytecode files

2:java Hello


CD \ Back to root directory

The src.zip in the bin directory is the Java source code
Data structures: Stacks, linked list arrays

&& Prior to | | Perform

Unary operator, two-tuple operator, three-operator


Switch compilation in float long char not jre1.7 before string is not a byte short int menu double row

Time complexity of the algorithm
Recursive algorithm, low running efficiency, time-consuming space

Simple data types are value passing
A complex data type is a reference pass

Binary Tree A parent node up to two child nodes with no child nodes for leaf nodes leaf node

For the root node is divided into the pre-order, the middle order, after the depth first traversal
There are pointers in Java, just don't let
Full binary tree, full two-fork tree
Ctrl+o View all methods of a class

The native (local) method cannot view the source code because different operating system native methods are different

The sort order of the Java Package sort () is a combination of quick sort and select sort
Binary find = Quick Find = two points find BinarySearch (Arr,key); It is better to sort the array first to ensure the accuracy of this method, if repeated, there is no guarantee of who was first discovered


Computer division efficiency is low, try to use shift

Arrays and classes are reference types

String composite type (reference type, class type) The underlying implementation is the basic data type char[] Array

Transaction isolation level, higher, more secure, but less efficient

Java Random (i)