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‎src/main/java/org/tj/OOP.java‎

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@@ -4,4 +4,7 @@
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* Created by 001 on 16/7/27.
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*/
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public class OOP {
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public static void main(String[] args) {
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System.out.println(Runtime.getRuntime().availableProcessors());
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}
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}

‎src/main/java/org/tj/algorithms/Sort.java‎

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@@ -22,7 +22,7 @@ public static void straightInsertionSort(int []a){
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static void quickSort(int [] a){
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quickSort(a,0,a.length-1);
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}
25-
// 快排 平均时间复杂度logN 最坏情况n2
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// 快排 平均时间复杂度 NlogN 最坏情况n2
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static void quickSort(int [] a,int begin,int end){
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int tmp = a[begin];
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int i = begin,j = end;

‎src/main/java/org/tj/algorithms/artofcoding/gcd/Euclidean.java‎

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package org.tj.algorithms.artofcoding.gcd;
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/**
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* Created by 001 on 16/8/25.
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*/
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public class Euclidean {
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// 欧几里德算法 又称辗转相除法 用来求两个数字的最大公因数
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static public int gcd(int m,int n){
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if (m<n){
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int t = m;
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m = n;
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n = t;
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}
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int k = m%n;
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while (k!=0){
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int t = n;
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n=k;
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m=t;
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k=m%n;
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}
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return n;
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}
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public static void main(String[] args) {
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System.out.println(gcd(544,119));
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}
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}

‎src/main/java/org/tj/algorithms/artofcoding/strings/SpinningString.java‎

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package org.tj.algorithms.artofcoding.strings;
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import org.tj.algorithms.strings.StringCutter;
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/**
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* Created by 001 on 16/8/25.
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*/
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public class SpinningString {
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// 定义字符串的左旋转操作:把字符串前面的若干个字符移动到字符串的尾部。
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// 如把字符串 abcdef 左旋转 2 位得到字符串 cdefab。 请实现字符串左旋转的函数,要求对长度为 n 的字符串操作的时间复杂度为 O(n),
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// 设计一个算法,把一个含有 N 个元素的数组循环右移 K 位,要求时间复杂度为 O(N), 且只允许使用两个附加变量。
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// 最直接解法 一位一位移 每移一位整个数组变动一次 先吧最后一位保存 然后每一位往前移一位
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// 时间复杂度为 n * (k%n)
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public static char[] rightShift(char[] n,int k){
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int length = n.length;
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k = k%length;
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k = k>0?k:length+k;
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for (int i=0;i<k;i++){
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char tmp = n[length-1];
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for (int j=length-1;j>0;j--){
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n[j] = n[j-1];
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}
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n[0] = tmp;
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}
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return n;
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}
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// abcf1234 右移四位变成1234abcf 那么直接吧后四位放倒字符串前面即可 时间复杂度n
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public static char[] rightShift2(char[] n,int k){
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int length = n.length;
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k = k%length;
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k = k>0?k:length+k;
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// k=length-k;
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// 构建一个新的char[]；
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char[] m = new char[length];
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for (int i=0;i<k;i++){
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m[i] = n[length-k+i];
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}
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for (int i=k;i<length;i++){
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m[i] = n[i-k];
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}
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return m;
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}
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// abcf1234 右移3位 先把前五位倒序 1fcba 后三位倒序432 再整个倒序 234abcf1
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public static char[] rightShift3(char[] n,int k){
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int length = n.length;
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k = k%length;
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k = k>0?k:length+k;
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for (int i=0;i<=(length-k-1)/2;i++){
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char tmp = n[i];
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n[i] = n[length-k-i-1];
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n[length-k-i-1] = tmp;
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}
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// System.out.println(String.valueOf(n));
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for (int i=length-k;i<=(2*length-k-1)/2;i++){
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char tmp = n[i];
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n[i] = n[length+(length-k)-1-i];
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n[length+(length-k)-1-i] = tmp;
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}
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// System.out.println(String.valueOf(n));
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// 反正n
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for (int i=0;i<=(length-1)/2;i++){
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char tmp = n[i];
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n[i] = n[length-1-i];
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n[length-1-i] = tmp;
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}
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return n;
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}
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public static void main(String[] args) {
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String s = "abcf1234";
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System.out.println(String.valueOf(rightShift(s.toCharArray(),-13)));
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System.out.println(String.valueOf(rightShift2(s.toCharArray(), -13)));
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System.out.println(String.valueOf(rightShift3(s.toCharArray(), -13)));
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}
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}

‎src/main/java/org/tj/algorithms/hash/DemoHash.java‎

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package org.tj.algorithms.hash;
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import java.util.HashMap;
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import java.util.Random;
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/**
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* Created by 001 on 16/8/25.
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*/
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public class DemoHash {
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// 随机生成n个数的数组
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public static int[] randIntArray(int n){
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Random random = new Random();
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int []array = new int[n];
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for (int i=0;i<n;i++){
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array[i] = random.nextInt();
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}
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return array;
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}
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// 直接对n取模算hash
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public static int[] modhash(int[] array,int n){
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int[] array1 = new int[16];
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int length = array.length;
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for (int i=0;i<length;i++){
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int index = array[i]%n;
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array1[index>0?index:-index]++;
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}
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return array1;
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}
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// 斐波那契（Fibonacci）散列法
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public static int[] fibonaccihash(int[] array,int n){
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int[] array1 = new int[16];
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int length = array.length;
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long f = Long.valueOf("2654435769");
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for (int i=0;i<length;i++){
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int index = (int) ((array[i]*f)%n);
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array1[index>0?index:-index]++;
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}
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return array1;
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}
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public static void printArray(int[] array){
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int length = array.length;
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for (int i=0;i<length;i++){
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System.out.print(array[i]+" ");
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}
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System.out.println();
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}
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public static void main(String[] args) {
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56+
// System.out.println(-5%4);
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int [] array = randIntArray(16);
58+
printArray(modhash(array,16));
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printArray(fibonaccihash(array,16));
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// long k = Long.valueOf("2654435769");
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// for (long i =0;i<100;i++){
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// System.out.println(((i*k)>>28) %16);
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// }
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}
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}

‎src/main/java/org/tj/designpatterns/creater/factory/abstractfactory/AbstractFactoryTest.java‎

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@@ -2,6 +2,9 @@
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import org.tj.designpatterns.creater.factory.simplefactory.Sender;
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import java.util.Arrays;
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import java.util.Calendar;
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58
/**
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* Created by 001 on 16/8/22.
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*/
@@ -14,5 +17,10 @@ public static void main(String[] args) {
1417
AbstractFactory factory1 = new MessageSenderFactory();
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Sender sender1 = factory1.produceSender();
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sender1.send();
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// Calendar.getInstance()
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// Arrays.asList()
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}
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}

‎src/main/java/org/tj/designpatterns/creater/singleton/HungrySingleton.java‎

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@@ -4,4 +4,12 @@
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* Created by 001 on 16/8/22.
55
*/
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public class HungrySingleton {
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// 饿汉式单例模式 线程安全 因为是在类加载的时候初始化的 但是缺点是 不管你用不用这个单例 每次启动都要实例化 会浪费资源和时间
9+
private HungrySingleton hungrySingleton = new HungrySingleton();
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public HungrySingleton getInstance(){
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return hungrySingleton;
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}
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715
}

‎src/main/java/org/tj/designpatterns/creater/singleton/LazySingleton.java‎

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@@ -3,25 +3,25 @@
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/**
44
* Created by 001 on 16/8/8.
55
*/
6-
public class Singleton {
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public class LazySingleton {
77

8-
private static Singleton instance = null;
8+
private static LazySingleton instance = null;
99

10-
private Singleton(){
10+
private LazySingleton(){
1111
System.out.println(instance);
1212
}
1313

1414
// 最基本的
15-
private static Singleton getInstance(){
15+
private static LazySingleton getInstance(){
1616
if (instance == null){
17-
instance = new Singleton();
17+
instance = new LazySingleton();
1818
}
1919
return instance;
2020
}
2121
// 每次去拿单例都要的获取锁等待 实际上只要第一次线程竞争的时候获取锁就行了
22-
private static synchronized Singleton getInstance1(){
22+
private static synchronized LazySingleton getInstance1(){
2323
if(instance == null){
24-
instance = new Singleton();
24+
instance = new LazySingleton();
2525
}
2626
return instance;
2727
}
@@ -30,11 +30,11 @@ private static synchronized Singleton getInstance1(){
3030
// 但是还会有一个问题 在JVM中 创建对象和赋值操作实分开进行的 并且不保证执行的先后顺序 也就是说有可能AB线程 ，A获取锁，根据JVM的优化
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// 机制，JVM有可能先给 Singletin 实例分配空间，然后就直接赋值给了instance变量，A线程离开同步块，B线程检测instance不为空，直接返回intance,有可能此时
3232
// JVM还没有完成初始化,所以B线程返回的为null;
33-
private static Singleton getInstance2(){
33+
private static LazySingleton getInstance2(){
3434
if (instance == null){
3535
synchronized (instance){
3636
if (instance == null){
37-
instance = new Singleton();
37+
instance = new LazySingleton();
3838
}
3939
}
4040
}

‎src/main/java/org/tj/study/thread/abcd/join/DemoJoin.java‎

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package org.tj.study.thread.abcd.join;
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/**
4+
* Created by 001 on 16/8/23.
5+
*/
6+
public class DemoJoin implements Runnable{
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Thread thread;
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10+
public DemoJoin(Thread thread){
11+
this.thread = thread;
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}
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public static void main(String[] args) {
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Thread thread1 = Thread.currentThread();
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Thread threadA = new Thread(new DemoJoin(thread1),"A");
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Thread threadB = new Thread(new DemoJoin(threadA),"B");
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Thread threadC = new Thread(new DemoJoin(threadB),"C");
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Thread threadD = new Thread(new DemoJoin(threadC),"D");
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threadA.start();
22+
threadB.start();
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threadC.start();
24+
threadD.start();
25+
}
26+
27+
@Override
28+
public void run() {
29+
try {
30+
thread.join();
31+
} catch (InterruptedException e) {
32+
e.printStackTrace();
33+
}
34+
System.out.println(Thread.currentThread().getName());
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}
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}

‎src/main/java/org/tj/study/thread/locks/DemoLock.java‎

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package org.tj.study.thread.locks;
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/**
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* Created by 001 on 16/8/24.
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*/
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public class DemoLock {
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}

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