Invincible-Backend-Study · JaeHongDev · Apr 27, 2023 · Apr 19, 2023
diff --git a/jaehong/chapter5/"Sample.java" b/jaehong/chapter5/"Sample.java"
diff --git a/jaehong/chapter5/--help b/jaehong/chapter5/--help
diff --git a/jaehong/chapter5/<classes> b/jaehong/chapter5/<classes>
diff --git a/jaehong/chapter5/<options> b/jaehong/chapter5/<options>
diff --git a/jaehong/chapter5/CompareInteger.java b/jaehong/chapter5/CompareInteger.java
@@ -0,0 +1,12 @@
+public class CompareInteger{
+
+
+	public static void main(String...args){
+
+		Integer i;
+		if(i == 42){
+			System.out.println(42);
+
+		}
+	}
+}
diff --git a/jaehong/chapter5/Compiled b/jaehong/chapter5/Compiled
diff --git a/jaehong/chapter5/Direction.class b/jaehong/chapter5/Direction.class
diff --git a/jaehong/chapter5/OperatorCasting.java b/jaehong/chapter5/OperatorCasting.java
@@ -0,0 +1,29 @@
+
+public class OperatorCasting{
+	public static void main(String ...args){
+		var operator = new OperatorCasting();
+		operator.casting();
+	}
+
+	public void casting(){
+
+		byte byteValue = 127;
+		short shortValue = byteValue; 
+
+		shortValue++;
+		System.out.println(shortValue);
+
+		byteValue=(byte)shortValue;
+
+		System.out.println(byteValue);
+
+		byte s1 = (byte)((int) 9);
+		byte s2 = (byte)((int) 10);
+
+		System.out.println(s1);
+		System.out.println(s2);
+		System.out.println(((byte) Long.MAX_VALUE));
+
+
+	}
+}
diff --git a/jaehong/chapter5/OperatorMultipleDivision.java b/jaehong/chapter5/OperatorMultipleDivision.java
@@ -0,0 +1,21 @@
+public class OperatorMultipleDivision{
+
+	public static void main(String...args){
+
+		OperatorMultipleDivision sample = new OperatorMultipleDivision();
+		sample.multipleDivision();
+	}
+
+
+	public void multipleDivision(){
+
+		int intValue1 =5;
+		int intValue2 =10;
+
+		int result = intValue1 * intValue2;
+		System.out.println(result);
+		result = intValue2 / intValue1;
+		System.out.println(result);
+
+	}
+}
diff --git a/jaehong/chapter5/OperatorPlusMinus.java b/jaehong/chapter5/OperatorPlusMinus.java
@@ -0,0 +1,19 @@
+public class OperatorPlusMinus{
+
+	public static void main(String ...args){
+		OperatorPlusMinus sample = new OperatorPlusMinus();	
+		sample.additive();
+	}
+
+	public void additive(){
+		int intValue1 = 5;
+		int intValue2 = 10;
+
+		int result=intValue1 + intValue2;
+
+		System.out.println(result);
+		result = intValue2 - intValue1;
+
+		System.out.println(result);
+	}
+}
diff --git a/jaehong/chapter5/OperatorTilde.java b/jaehong/chapter5/OperatorTilde.java
@@ -0,0 +1,12 @@
+public class OperatorTilde{
+
+	public static void main(String ...args){
+		int num = 1;
+		int a = num++ + --num;
+		System.out.println(a);
+
+
+		final var result = OperatorTilde > OperatorTilde;
+
+	}
+}
diff --git a/jaehong/chapter5/Sample b/jaehong/chapter5/Sample
diff --git a/jaehong/chapter5/Sample$1.class b/jaehong/chapter5/Sample$1.class
diff --git a/jaehong/chapter5/Sample(); b/jaehong/chapter5/Sample();
diff --git a/jaehong/chapter5/Sample.class b/jaehong/chapter5/Sample.class
diff --git a/jaehong/chapter5/Sample.java b/jaehong/chapter5/Sample.java
@@ -0,0 +1,42 @@
+public class Sample{
+
+	public static void main(String...args){
+		System.out.println(ifStatement(Direction.TOP));
+		System.out.println(ifStatement(Direction.BOTTOM));
+		System.out.println(ifStatement(Direction.LEFT));
+		System.out.println(ifStatement(Direction.RIGHT));
+	}
+
+	public static int ifStatement(Direction dr){
+		if(dr == Direction.TOP){
+			return 1;
+		}
+		if(dr == Direction.BOTTOM){
+			return 2;
+		}
+		if(dr == Direction.LEFT){
+			return 3;
+		}
+		if(dr == Direction.RIGHT){
+			return 4;
+		}
+		return 0;
+	}
+
+	public static int switchStatement(Direction dr){
+		return switch(dr){
+			case TOP -> 1;
+			case BOTTOM -> 2;
+			case LEFT -> 3;
+			case RIGHT -> 4;
+		};
+	}
+}
+
+
+enum Direction{
+	TOP,
+	BOTTOM,
+	LEFT,
+	RIGHT;
+}
diff --git a/jaehong/chapter5/Usage: b/jaehong/chapter5/Usage:
diff --git a/jaehong/chapter5/a b/jaehong/chapter5/a
diff --git a/jaehong/chapter5/a.txt b/jaehong/chapter5/a.txt
@@ -0,0 +1,207 @@
+Classfile /Users/jaehong/Documents/java-basic-1/jaehong/chapter5/Sample.class
+  Last modified 2023. 4. 17.; size 1046 bytes
+  SHA-256 checksum 0ed37afb8327701d44e6d0c60e64743dd2622cb7b80a8df03d84081ff0e419f9
+  Compiled from "Sample.java"
+public class Sample
+  minor version: 0
+  major version: 62
+  flags: (0x0021) ACC_PUBLIC, ACC_SUPER
+  this_class: #20                         // Sample
+  super_class: #2                         // java/lang/Object
+  interfaces: 0, fields: 0, methods: 4, attributes: 3
+Constant pool:
+   #1 = Methodref          #2.#3          // java/lang/Object."<init>":()V
+   #2 = Class              #4             // java/lang/Object
+   #3 = NameAndType        #5:#6          // "<init>":()V
+   #4 = Utf8               java/lang/Object
+   #5 = Utf8               <init>
+   #6 = Utf8               ()V
+   #7 = Fieldref           #8.#9          // java/lang/System.out:Ljava/io/PrintStream;
+   #8 = Class              #10            // java/lang/System
+   #9 = NameAndType        #11:#12        // out:Ljava/io/PrintStream;
+  #10 = Utf8               java/lang/System
+  #11 = Utf8               out
+  #12 = Utf8               Ljava/io/PrintStream;
+  #13 = Fieldref           #14.#15        // Direction.TOP:LDirection;
+  #14 = Class              #16            // Direction
+  #15 = NameAndType        #17:#18        // TOP:LDirection;
+  #16 = Utf8               Direction
+  #17 = Utf8               TOP
+  #18 = Utf8               LDirection;
+  #19 = Methodref          #20.#21        // Sample.ifStatement:(LDirection;)I
+  #20 = Class              #22            // Sample
+  #21 = NameAndType        #23:#24        // ifStatement:(LDirection;)I
+  #22 = Utf8               Sample
+  #23 = Utf8               ifStatement
+  #24 = Utf8               (LDirection;)I
+  #25 = Methodref          #26.#27        // java/io/PrintStream.println:(I)V
+  #26 = Class              #28            // java/io/PrintStream
+  #27 = NameAndType        #29:#30        // println:(I)V
+  #28 = Utf8               java/io/PrintStream
+  #29 = Utf8               println
+  #30 = Utf8               (I)V
+  #31 = Fieldref           #14.#32        // Direction.BOTTOM:LDirection;
+  #32 = NameAndType        #33:#18        // BOTTOM:LDirection;
+  #33 = Utf8               BOTTOM
+  #34 = Fieldref           #14.#35        // Direction.LEFT:LDirection;
+  #35 = NameAndType        #36:#18        // LEFT:LDirection;
+  #36 = Utf8               LEFT
+  #37 = Fieldref           #14.#38        // Direction.RIGHT:LDirection;
+  #38 = NameAndType        #39:#18        // RIGHT:LDirection;
+  #39 = Utf8               RIGHT
+  #40 = Fieldref           #41.#42        // Sample$1.$SwitchMap$Direction:[I
+  #41 = Class              #43            // Sample$1
+  #42 = NameAndType        #44:#45        // $SwitchMap$Direction:[I
+  #43 = Utf8               Sample$1
+  #44 = Utf8               $SwitchMap$Direction
+  #45 = Utf8               [I
+  #46 = Methodref          #14.#47        // Direction.ordinal:()I
+  #47 = NameAndType        #48:#49        // ordinal:()I
+  #48 = Utf8               ordinal
+  #49 = Utf8               ()I
+  #50 = Class              #51            // java/lang/IncompatibleClassChangeError
+  #51 = Utf8               java/lang/IncompatibleClassChangeError
+  #52 = Methodref          #50.#3         // java/lang/IncompatibleClassChangeError."<init>":()V
+  #53 = Utf8               Code
+  #54 = Utf8               LineNumberTable
+  #55 = Utf8               main
+  #56 = Utf8               ([Ljava/lang/String;)V
+  #57 = Utf8               StackMapTable
+  #58 = Utf8               switchStatement
+  #59 = Utf8               SourceFile
+  #60 = Utf8               Sample.java
+  #61 = Utf8               NestMembers
+  #62 = Utf8               InnerClasses
+{
+  public Sample();
+    descriptor: ()V
+    flags: (0x0001) ACC_PUBLIC
+    Code:
+      stack=1, locals=1, args_size=1
+         0: aload_0
+         1: invokespecial #1                  // Method java/lang/Object."<init>":()V
+         4: return
+      LineNumberTable:
+        line 1: 0
+
+  public static void main(java.lang.String...);
+    descriptor: ([Ljava/lang/String;)V
+    flags: (0x0089) ACC_PUBLIC, ACC_STATIC, ACC_VARARGS
+    Code:
+      stack=2, locals=1, args_size=1
+         0: getstatic     #7                  // Field java/lang/System.out:Ljava/io/PrintStream;
+         3: getstatic     #13                 // Field Direction.TOP:LDirection;
+         6: invokestatic  #19                 // Method ifStatement:(LDirection;)I
+         9: invokevirtual #25                 // Method java/io/PrintStream.println:(I)V
+        12: getstatic     #7                  // Field java/lang/System.out:Ljava/io/PrintStream;
+        15: getstatic     #31                 // Field Direction.BOTTOM:LDirection;
+        18: invokestatic  #19                 // Method ifStatement:(LDirection;)I
+        21: invokevirtual #25                 // Method java/io/PrintStream.println:(I)V
+        24: getstatic     #7                  // Field java/lang/System.out:Ljava/io/PrintStream;
+        27: getstatic     #34                 // Field Direction.LEFT:LDirection;
+        30: invokestatic  #19                 // Method ifStatement:(LDirection;)I
+        33: invokevirtual #25                 // Method java/io/PrintStream.println:(I)V
+        36: getstatic     #7                  // Field java/lang/System.out:Ljava/io/PrintStream;
+        39: getstatic     #37                 // Field Direction.RIGHT:LDirection;
+        42: invokestatic  #19                 // Method ifStatement:(LDirection;)I
+        45: invokevirtual #25                 // Method java/io/PrintStream.println:(I)V
+        48: return
+      LineNumberTable:
+        line 4: 0
+        line 5: 12
+        line 6: 24
+        line 7: 36
+        line 8: 48
+
+  public static int ifStatement(Direction);
+    descriptor: (LDirection;)I
+    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
+    Code:
+      stack=2, locals=1, args_size=1
+         0: aload_0
+         1: getstatic     #13                 // Field Direction.TOP:LDirection;
+         4: if_acmpne     9
+         7: iconst_1
+         8: ireturn
+         9: aload_0
+        10: getstatic     #31                 // Field Direction.BOTTOM:LDirection;
+        13: if_acmpne     18
+        16: iconst_2
+        17: ireturn
+        18: aload_0
+        19: getstatic     #34                 // Field Direction.LEFT:LDirection;
+        22: if_acmpne     27
+        25: iconst_3
+        26: ireturn
+        27: aload_0
+        28: getstatic     #37                 // Field Direction.RIGHT:LDirection;
+        31: if_acmpne     36
+        34: iconst_4
+        35: ireturn
+        36: iconst_0
+        37: ireturn
+      LineNumberTable:
+        line 11: 0
+        line 12: 7
+        line 14: 9
+        line 15: 16
+        line 17: 18
+        line 18: 25
+        line 20: 27
+        line 21: 34
+        line 23: 36
+      StackMapTable: number_of_entries = 4
+        frame_type = 9 /* same */
+        frame_type = 8 /* same */
+        frame_type = 8 /* same */
+        frame_type = 8 /* same */
+
+  public static int switchStatement(Direction);
+    descriptor: (LDirection;)I
+    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
+    Code:
+      stack=2, locals=1, args_size=1
+         0: getstatic     #40                 // Field Sample$1.$SwitchMap$Direction:[I
+         3: aload_0
+         4: invokevirtual #46                 // Method Direction.ordinal:()I
+         7: iaload
+         8: tableswitch   { // 1 to 4
+                       1: 48
+                       2: 52
+                       3: 56
+                       4: 60
+                 default: 40
+            }
+        40: new           #50                 // class java/lang/IncompatibleClassChangeError
+        43: dup
+        44: invokespecial #52                 // Method java/lang/IncompatibleClassChangeError."<init>":()V
+        47: athrow
+        48: iconst_1
+        49: goto          61
+        52: iconst_2
+        53: goto          61
+        56: iconst_3
+        57: goto          61
+        60: iconst_4
+        61: ireturn
+      LineNumberTable:
+        line 27: 0
+        line 28: 48
+        line 29: 52
+        line 30: 56
+        line 31: 60
+        line 27: 61
+      StackMapTable: number_of_entries = 6
+        frame_type = 40 /* same */
+        frame_type = 7 /* same */
+        frame_type = 3 /* same */
+        frame_type = 3 /* same */
+        frame_type = 3 /* same */
+        frame_type = 64 /* same_locals_1_stack_item */
+          stack = [ int ]
+}
+SourceFile: "Sample.java"
+NestMembers:
+  Sample$1
+InnerClasses:
+  static #41;                             // class Sample$1
diff --git a/jaehong/chapter5/class b/jaehong/chapter5/class
diff --git a/jaehong/chapter5/for b/jaehong/chapter5/for
diff --git a/jaehong/chapter5/from b/jaehong/chapter5/from
diff --git a/jaehong/chapter5/ifStatement(Direction); b/jaehong/chapter5/ifStatement(Direction);
diff --git a/jaehong/chapter5/int b/jaehong/chapter5/int
diff --git a/jaehong/chapter5/javap b/jaehong/chapter5/javap
diff --git a/jaehong/chapter5/list b/jaehong/chapter5/list
diff --git a/jaehong/chapter5/main(java.lang.String...); b/jaehong/chapter5/main(java.lang.String...);
diff --git a/jaehong/chapter5/of b/jaehong/chapter5/of
diff --git a/jaehong/chapter5/options b/jaehong/chapter5/options
diff --git a/jaehong/chapter5/possible b/jaehong/chapter5/possible
diff --git a/jaehong/chapter5/public b/jaehong/chapter5/public
diff --git a/jaehong/chapter5/static b/jaehong/chapter5/static
diff --git a/jaehong/chapter5/switchStatement(Direction); b/jaehong/chapter5/switchStatement(Direction);
diff --git a/jaehong/chapter5/untitled/build.gradle b/jaehong/chapter5/untitled/build.gradle
@@ -0,0 +1,19 @@
+plugins {
+    id 'java'
+}
+
+group 'org.example'
+version '1.0-SNAPSHOT'
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.1'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.1'
+}
+
+test {
+    useJUnitPlatform()
+}
diff --git a/jaehong/chapter5/untitled/gradle/wrapper/gradle-wrapper.jar b/jaehong/chapter5/untitled/gradle/wrapper/gradle-wrapper.jar
diff --git a/jaehong/chapter5/untitled/gradle/wrapper/gradle-wrapper.properties b/jaehong/chapter5/untitled/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.5.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists