update test demo

src/test/java/haidnor/jvm/test/TestJVM.java

@@ -72,6 +72,26 @@ public class TestJVM {
         runMainClass(Demo7.class);
     }
 
+    @Test
+    public void demo_while() throws Exception {
+        runMainClass(demo_while.class);
+    }
+
+    @Test
+    public void demo_doWhile() throws Exception {
+        runMainClass(demo_doWhile.class);
+    }
+
+    @Test
+    public void demo_for() throws Exception {
+        runMainClass(demo_for.class);
+    }
+
+    @Test
+    public void demo_foreach() throws Exception {
+        runMainClass(demo_foreach.class);
+    }
+
     @Test
     public void test_8() throws Exception {
         runMainClass(Demo8.class);

src/test/java/haidnor/jvm/test/demo/demo_doWhile.java

@@ -0,0 +1,27 @@
+package haidnor.jvm.test.demo;
+
+public class demo_doWhile {
+    public static void main(String[] args) {
+        int a = 0;
+        do {
+            a++;
+        } while (a < 2);
+        System.out.println(a);
+    }
+}
+
+/*
+main(String[] args):
+     0 iconst_0
+     1 istore_1
+
+     2 iinc 1 by 1
+     5 iload_1
+     6 iconst_2
+     7 if_icmplt 2 (-5)      < while (a < 2); 符合条件则向前跳转
+
+    10 getstatic #7 <java/lang/System.out : Ljava/io/PrintStream;>
+    13 iload_1
+    14 invokevirtual #13 <java/io/PrintStream.println : (I)V>
+    17 return
+ */

src/test/java/haidnor/jvm/test/demo/demo_exception_3.java

@@ -21,12 +21,12 @@ public class demo_exception_3 {
 }
 /*
 main(String[] args)
-    0 iconst_0
-    1 istore_1
-    2 iload_1
-    3 invokestatic #7 <haidnor/jvm/test/demo/demo_exception.fun : (I)V>
-    6 goto 18 (+12)
-    9 astore_2
+     0 iconst_0
+     1 istore_1
+     2 iload_1
+     3 invokestatic #7 <haidnor/jvm/test/demo/demo_exception_3.fun : (I)V>
+     6 goto 18 (+12)
+     9 astore_2
     10 getstatic #15 <java/lang/System.out : Ljava/io/PrintStream;>
     13 ldc #21 <catch Exception>
     15 invokevirtual #23 <java/io/PrintStream.println : (Ljava/lang/String;)V>
@@ -40,12 +40,11 @@ main(String[] args)
 
 
 fun(int a)
-     0 iload_0
-     1 ifne 12 (+11)
-     4 new #29 <java/lang/ArithmeticException>
-     7 dup
-     8 invokespecial #31 <java/lang/ArithmeticException.<init> : ()V>
-    11 athrow
-    12 return
+    0 getstatic #15 <java/lang/System.out : Ljava/io/PrintStream;>
+    3 iconst_1
+    4 iload_0
+    5 idiv
+    6 invokevirtual #29 <java/io/PrintStream.println : (I)V>
+    9 return
 
 */

src/test/java/haidnor/jvm/test/demo/demo_exception_4.java

@@ -21,12 +21,12 @@ public class demo_exception_4 {
 }
 /*
 main(String[] args)
-    0 iconst_0
-    1 istore_1
-    2 iload_1
-    3 invokestatic #7 <haidnor/jvm/test/demo/demo_exception.fun : (I)V>
-    6 goto 18 (+12)
-    9 astore_2
+     0 iconst_0
+     1 istore_1
+     2 iload_1
+     3 invokestatic #7 <haidnor/jvm/test/demo/demo_exception_4.fun : (I)V>
+     6 goto 18 (+12)
+     9 astore_2
     10 getstatic #15 <java/lang/System.out : Ljava/io/PrintStream;>
     13 ldc #21 <catch Exception>
     15 invokevirtual #23 <java/io/PrintStream.println : (Ljava/lang/String;)V>
@@ -40,12 +40,11 @@ main(String[] args)
 
 
 fun(int a)
-     0 iload_0
-     1 ifne 12 (+11)
-     4 new #29 <java/lang/ArithmeticException>
-     7 dup
-     8 invokespecial #31 <java/lang/ArithmeticException.<init> : ()V>
-    11 athrow
-    12 return
+    0 getstatic #15 <java/lang/System.out : Ljava/io/PrintStream;>
+    3 iconst_1
+    4 iload_0
+    5 idiv
+    6 invokevirtual #29 <java/io/PrintStream.println : (I)V>
+    9 return
 
 */

src/test/java/haidnor/jvm/test/demo/demo_for.java

@@ -0,0 +1,31 @@
+package haidnor.jvm.test.demo;
+
+public class demo_for {
+    public static void main(String[] args) {
+        int a = 0;
+        for (int i = 0; i < 3; i++) {
+            a++;
+        }
+        System.out.println(a);
+    }
+}
+
+/*
+main(String[] args):
+     0 iconst_0      < int a = 0
+     1 istore_1
+     2 iconst_0      < int i =0
+     3 istore_2
+
+     4 iload_2
+     5 iconst_3                < 比较值3
+     6 if_icmpge 18 (+12)      < (i < 3)
+     9 iinc 1 by 1             < a++
+    12 iinc 2 by 1             < i++
+    15 goto 4 (-11)            < 向前跳转代码
+
+    18 getstatic #7 <java/lang/System.out : Ljava/io/PrintStream;>
+    21 iload_1
+    22 invokevirtual #13 <java/io/PrintStream.println : (I)V>
+    25 return
+ */

src/test/java/haidnor/jvm/test/demo/demo_foreach.java

@@ -0,0 +1,62 @@
+package haidnor.jvm.test.demo;
+
+public class demo_foreach {
+    public static void main(String[] args) {
+        int[] arr = new int[]{999, 333};
+        for (int i : arr) {
+            System.out.println(i);
+        }
+    }
+}
+
+/*
+main(String[] args):
+     0 iconst_2              < 操作数栈压入2,这个是 arr[] 的长度
+     1 newarray 10 (int)     < 创建数组
+     3 dup
+
+     4 iconst_0
+     5 sipush 999
+     8 iastore               < arr[0] = 999
+
+     9 dup                   < 复制栈顶的 arr[], 压入操作数栈
+
+    10 iconst_1
+    11 sipush 333
+    14 iastore                < arr[1] = 333
+
+    15 astore_1
+    16 aload_1
+    17 astore_2
+    18 aload_2
+    19 arraylength
+    20 istore_3
+    21 iconst_0
+    22 istore 4
+
+    24 iload 4
+    26 iload_3
+    27 if_icmpge 50 (+23)
+    30 aload_2
+    31 iload 4
+    33 iaload
+    34 istore 5
+    36 getstatic #7 <java/lang/System.out : Ljava/io/PrintStream;>
+    39 iload 5
+    41 invokevirtual #13 <java/io/PrintStream.println : (I)V>
+    44 iinc 4 by 1
+    47 goto 24 (-23)
+
+    50 return
+
++--------+-------+--------+--------+-----------+-------------------------+
+| Nr.    | 起始PC | 长度   | 序号    | 名字       | 描述符(存储类型)          |
++--------+-------+--------+--------+-----------+-------------------------+
+| 0      | 0     | 51     | 0      | args      | [Ljava/lang/String;     |
++--------+-------+--------+--------+-----------+-------------------------+
+| 1      | 16    | 35     | 1      | arr       | [I                      |
++--------+-------+--------+--------+-----------+-------------------------+
+| 2      | 36    | 8      | 5      | i         | I                       |
++--------+-------+--------+--------+-----------+-------------------------+
+
+ */

src/test/java/haidnor/jvm/test/demo/demo_while.java

@@ -0,0 +1,29 @@
+package haidnor.jvm.test.demo;
+
+public class demo_while {
+    public static void main(String[] args) {
+        int a = 0;
+        while (a < 2) {
+            a++;
+        }
+        System.out.println(a);
+    }
+}
+
+/*
+main(String[] args):
+     0 iconst_0
+     1 istore_1
+     2 iload_1
+     3 iconst_2
+
+     4 if_icmpge 13 (+9)    < 符合条件就进入循环体
+     7 iinc 1 by 1          < a++
+    10 goto 2 (-8)          < 向前跳转指令
+
+    13 getstatic #7 <java/lang/System.out : Ljava/io/PrintStream;>
+    16 iload_1
+    17 invokevirtual #13 <java/io/PrintStream.println : (I)V>
+    20 return
+
+ */