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--- java:javap [2023/04/12 12:04] – odefta
+++ java:javap [2023/07/04 16:36] (current) – external edit 127.0.0.1
@@ Line 45: / Line 45: @@
 }
 </code>
+<note tip>We want to check if all the generic types are erased after the compilation.</note>
-We want to check if all the generic types are erased after the compilation.\\
 <note important>Be sure that the javap tool is added to the PATH environment variable before using it.
 It is located in the JAVA_HOME\bin folder.
@@ Line 55: / Line 54: @@
 C:\JavaProject\src\main\java> javap -cp ../../../target/classes -c ro.medjava.generics.Erasure
 </code>
+<note tip>-c parameter is used to display the disassembled code.</note>
 Result:
 <code>
 public ro.medjava.generics.Erasure();
-    Code:
+  Code:
 : aload_0
-: invokespecial #1                  // Method java/lang/Object."<init>":()V
+: invokespecial #1                // Method java/lang/Object."<init>":()V
 : return
@@ Line 74: / Line 75: @@
   public static void main(java.lang.String[]);
     Code:
-: new           #2                  // class java/util/ArrayList
+: new           #2               // class java/util/ArrayList
 : dup
 : iconst_1
-: anewarray     #3                  // class java/lang/String
+: anewarray     #3               // class java/lang/String
 : dup
 : iconst_0
-: ldc           #4                  // String Fred
+: ldc           #4               // String Fred
 : aastore
-: invokestatic  #5                  // Method java/util/Arrays.asList:([Ljava/lang/Object;)Ljava/util/List;
+: invokestatic  #5               // Method java/util/Arrays.asList:([Ljava/lang/Object;)Ljava/util/List;
-: invokespecial #6                  // Method java/util/ArrayList."<init>":(Ljava/util/Collection;)V
+: invokespecial #6               // Method java/util/ArrayList."<init>":(Ljava/util/Collection;)V
-: invokestatic  #7                  // Method doStuff2:(Ljava/util/List;)V
+: invokestatic  #7               // Method doStuff2:(Ljava/util/List;)V
 : return
 </code>
+As we can see in the parameter list of doStuff1 and doStuff2 methods, the generic types survived after compilation.\\
+Some consistency checking information still remains in the binary.\\
+But in the main method, the array list passed to the doStuff2 method does not contain any generic type after compilation.
+===== Use javap in Intellij IDEA =====
+Install the plugin "Class Decompile." (File / Settings / Plugins)
+{{:java:pasted:20230412-152124.png}}
+{{:java:pasted:20230412-152141.png}}
+Next, right click on your class and select "Show Decompile Code" option.
+Result:
+{{:java:javap_erasure.png?nolink&1536×648}}