JVM第三周作业

group24/1148285693/learning2017/common/src/main/java/me/lzb/common/utils/ByteUtils.java

@@ -0,0 +1,26 @@
+package me.lzb.common.utils;
+
+/**
+ * Created by LZB on 2017/4/14.
+ */
+public class ByteUtils {
+
+    public static String byteToHexString(byte[] codes ){
+        StringBuffer buffer = new StringBuffer();
+        for(int i=0;i<codes.length;i++){
+            byte b = codes[i];
+            int value = b & 0xFF;
+            String strHex = Integer.toHexString(value);
+            if(strHex.length()< 2){
+                strHex = "0" + strHex;
+            }
+            buffer.append(strHex);
+        }
+        return buffer.toString();
+    }
+
+    public static int byteToInt(byte[] codes){
+        String s1 = byteToHexString(codes);
+        return Integer.valueOf(s1, 16).intValue();
+    }
+}

group24/1148285693/learning2017/mini-jvm/src/main/java/me/lzb/utils/FileUtils.java → group24/1148285693/learning2017/common/src/main/java/me/lzb/common/utils/FileUtils.java

@@ -1,4 +1,4 @@
-package me.lzb.utils;
+package me.lzb.common.utils;
 
 import java.io.*;
 
@@ -15,17 +15,25 @@ public class FileUtils {
      * @return true false
      */
     public static boolean isFileExist(String path, String name) {
-        File file = new File(path + "\\" + name);
+        return isFileExist(path + File.separator + name);
+    }
+
+    public static boolean isFileExist(String f) {
+        File file = new File(f);
         return file.exists();
     }
 
+
     /**
      * 读取文件为二进制数组
      * @param clzFileName 文件路径
      * @return 数组
      * @throws IOException
      */
     public static byte[] readByteCodes(String clzFileName) throws IOException {
+        if(!isFileExist(clzFileName)){
+            return null;
+        }
 
         File f = new File(clzFileName);
 

group24/1148285693/learning2017/mini-jvm/src/main/java/me/lzb/utils/StringUtils.java → group24/1148285693/learning2017/common/src/main/java/me/lzb/common/utils/StringUtils.java

@@ -1,7 +1,8 @@
-package me.lzb.utils;
+package me.lzb.common.utils;
 
 /**
  * Created by LZB on 2017/4/4.
  */
 public class StringUtils extends org.apache.commons.lang3.StringUtils {
+
 }

group24/1148285693/learning2017/learning-basic/pom.xml

@@ -18,5 +18,10 @@
 
 
     <dependencies>
+        <dependency>
+            <groupId>me.lzb</groupId>
+            <artifactId>common</artifactId>
+            <version>1.0</version>
+        </dependency>
     </dependencies>
 </project>

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/datastructure/ArrayList.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/ArrayList.java

@@ -1,4 +1,4 @@
-package me.lzb.datastructure;
+package me.lzb.basic;
 
 /**
  * 简易ArrayList

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/datastructure/ArrayUtil.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/ArrayUtil.java

@@ -1,4 +1,4 @@
-package me.lzb.datastructure;
+package me.lzb.basic;
 
 public class ArrayUtil {
 

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/datastructure/BinaryTreeNode.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/BinaryTreeNode.java

@@ -1,4 +1,4 @@
-package me.lzb.datastructure;
+package me.lzb.basic;
 
 /**
  * 左边比父节点小，右边比父节点大

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/InfixExpr.java

@@ -0,0 +1,161 @@
+package me.lzb.basic;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Stack;
+
+/**
+ * Created by LZB on 2017/4/15.
+ */
+public class InfixExpr {
+
+
+    private String expr;
+
+    public InfixExpr(String expr) {
+        this.expr = expr;
+    }
+
+    public float evaluate() {
+
+        List<Node> list = processExpr();
+
+        Stack<String> symbolStack = new Stack<>();
+        Stack<Float> numberStack = new Stack<>();
+
+        boolean calLevel2 = false;
+        for (Node n : list) {
+            if (n.isNumber) {
+                numberStack.push(n.number);
+                if (calLevel2) {
+                    calculate(symbolStack, numberStack, false);
+                    calLevel2 = false;
+                }
+            } else {
+                symbolStack.push(n.symbol);
+
+                if (n.isLevel2()) {
+                    calLevel2 = true;
+                }
+            }
+        }
+
+
+        Stack<Float> tn = new Stack<>();
+        int nsize = numberStack.size();
+        for (int i = 0; i < nsize; i++) {
+            tn.push(numberStack.pop());
+        }
+
+        numberStack = tn;
+
+
+        Stack<String> ts = new Stack<>();
+        int ssize = symbolStack.size();
+        for (int i = 0; i < ssize; i++) {
+            ts.push(symbolStack.pop());
+        }
+
+        symbolStack = ts;
+
+
+        while (!symbolStack.isEmpty()) {
+            calculate(symbolStack, numberStack, true);
+        }
+
+
+        return numberStack.pop();
+    }
+
+
+
+    private List<Node> processExpr() {
+        List<Node> list = new ArrayList<>();
+        char[] array = this.expr.toCharArray();
+        String number = "";
+        for (int i = 0; i < array.length; i++) {
+            if (Character.isDigit(array[i])) {
+                number = number + String.valueOf(array[i]);
+            } else {
+                Node num = new Node(Float.valueOf(number), null, true, -1);
+                number = "";
+                int calLevel = "+-".indexOf(array[i]) >= 0 ? 1 : 2;
+                Node sym = new Node(0, String.valueOf(array[i]), false, calLevel);
+                list.add(num);
+                list.add(sym);
+            }
+        }
+
+        Node num = new Node(Float.valueOf(number), null, true, -1);
+        list.add(num);
+        return list;
+    }
+
+
+    private void calculate(Stack<String> symbolStack, Stack<Float> numberStack, boolean isRe) {
+        if (symbolStack.isEmpty()) {
+            return;
+        }
+
+
+        String symbole = symbolStack.pop();
+
+        float right;
+        float left;
+
+        if(isRe){
+            left = numberStack.pop();
+            right = numberStack.pop();
+        }else {
+            right = numberStack.pop();
+            left = numberStack.pop();
+        }
+
+
+
+        float r = calculate(symbole, left, right);
+
+        numberStack.push(r);
+    }
+
+
+    private float calculate(String symbol, float left, float right) {
+        if ("+".equals(symbol)) {
+            return left + right;
+        }
+
+        if ("-".equals(symbol)) {
+            return left - right;
+        }
+
+        if ("*".equals(symbol)) {
+            return left * right;
+        }
+
+        if ("/".equals(symbol)) {
+            return left / right;
+        }
+
+        return 0;
+    }
+
+
+    private class Node {
+        float number;
+        String symbol;
+        boolean isNumber;
+        int calLevel;//加减1，乘除2
+
+        public Node(float number, String symbol, boolean isNumber, int calLevel) {
+            this.number = number;
+            this.symbol = symbol;
+            this.isNumber = isNumber;
+            this.calLevel = calLevel;
+        }
+
+        private boolean isLevel2() {
+            return calLevel == 2;
+        }
+    }
+
+}

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/datastructure/Iterator.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/Iterator.java

@@ -1,4 +1,4 @@
-package me.lzb.datastructure;
+package me.lzb.basic;
 
 /**
  * Created by LZB on 2017/3/11.

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/algorithm/LRUPageFrame.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/LRUPageFrame.java

@@ -1,4 +1,4 @@
-package me.lzb.algorithm;
+package me.lzb.basic;
 
 /**
  * 用双向链表实现LRU算法

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/datastructure/LinkedList.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/LinkedList.java

@@ -1,4 +1,4 @@
-package me.lzb.datastructure;
+package me.lzb.basic;
 
 
 /**

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/datastructure/List.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/List.java

@@ -1,4 +1,4 @@
-package me.lzb.datastructure;
+package me.lzb.basic;
 
 /**
  * list接口

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/datastructure/Queue.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/Queue.java

@@ -1,4 +1,4 @@
-package me.lzb.datastructure;
+package me.lzb.basic;
 
 /**
  * 先进先出

group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/datastructure/Stack.java → group24/1148285693/learning2017/learning-basic/src/main/java/me/lzb/basic/Stack.java

@@ -1,4 +1,4 @@
-package me.lzb.datastructure;
+package me.lzb.basic;
 
 /**
  * 先进后出