From 42276ed18a21a1da2b7e3c61804f68459f4f73b0 Mon Sep 17 00:00:00 2001
From: MeenaGawande <45625809+MeenaGawande@users.noreply.github.com>
Date: Sat, 7 Nov 2020 20:48:40 +0530
Subject: [PATCH] [BAEL-4556] How to Check if a Java Program Is Running in
 64-Bit JVM or 32-Bit JVM (#10139)

* How to Check if a Java Program Is Running in 64-Bit JVM or 32-Bit JVM

How to Check if a Java Program Is Running in 64-Bit JVM or 32-Bit JVM

* baeldung-articlesBAEL-4556 How can I tell if I'm running in 64-bit JVM or 32-bit JVM

Changes as per review comments .
1.Package Name change
2.Variable change from static to instance
3.Test Method name change

* Update JVMBitVersionUnitTest.java

[BAEL-4556] How to Check if a Java Program Is Running in 64-Bit JVM or 32-Bit JVM

* [BAEL-4556]Added code and Junits for JVMBitVersion

* [BAEL-4556]Removed code and Junits for os.arch property to check JVMBitVersion

Co-authored-by: MeenaGawande <MeenaGawande@users.noreply.github.com>
---
 .../baeldung/jvmbitversion/JVMBitVersion.java | 24 ++++++++++
 .../jvmbitversion/JVMBitVersionUnitTest.java  | 46 +++++++++++++++++++
 2 files changed, 70 insertions(+)
 create mode 100644 java-native/src/main/java/com/baeldung/jvmbitversion/JVMBitVersion.java
 create mode 100644 java-native/src/test/java/com/baeldung/jvmbitversion/JVMBitVersionUnitTest.java

diff --git a/java-native/src/main/java/com/baeldung/jvmbitversion/JVMBitVersion.java b/java-native/src/main/java/com/baeldung/jvmbitversion/JVMBitVersion.java
new file mode 100644
index 0000000000..63684fec49
--- /dev/null
+++ b/java-native/src/main/java/com/baeldung/jvmbitversion/JVMBitVersion.java
@@ -0,0 +1,24 @@
+package com.baeldung.jvmbitversion;
+
+import com.sun.jna.Platform;
+
+public class JVMBitVersion {
+
+    public String getUsingSystemClass() {
+        return System.getProperty("sun.arch.data.model") + "-bit";
+    }
+
+    public String getUsingNativeClass() {
+        if (com.sun.jna.Native.POINTER_SIZE == 8) {
+            return "64-bit";
+        } else if (com.sun.jna.Native.POINTER_SIZE == 4) {
+            return "32-bit";
+        } else
+            return "unknown";
+    }
+
+    public boolean getUsingPlatformClass() {
+        return (Platform.is64Bit());
+    }
+
+}
diff --git a/java-native/src/test/java/com/baeldung/jvmbitversion/JVMBitVersionUnitTest.java b/java-native/src/test/java/com/baeldung/jvmbitversion/JVMBitVersionUnitTest.java
new file mode 100644
index 0000000000..152008e5e2
--- /dev/null
+++ b/java-native/src/test/java/com/baeldung/jvmbitversion/JVMBitVersionUnitTest.java
@@ -0,0 +1,46 @@
+package com.baeldung.jvmbitversion;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import com.baeldung.jvmbitversion.JVMBitVersion;
+import com.sun.jna.Platform;
+
+public class JVMBitVersionUnitTest {
+
+    private JVMBitVersion jvmVersion;
+
+    @Before
+    public void setup() {
+        jvmVersion = new JVMBitVersion();
+    }
+
+    @Test
+    public void whenUsingSystemClass_thenOutputIsAsExpected() {
+        if (System.getProperty("sun.arch.data.model") == "64") {
+            assertEquals("64-bit", jvmVersion.getUsingSystemClass());
+        } else if (System.getProperty("sun.arch.data.model") == "32") {
+            assertEquals("32-bit", jvmVersion.getUsingSystemClass());
+        }
+    }
+    
+    @Test
+    public void whenUsingNativeClass_thenResultIsAsExpected() {
+        if (com.sun.jna.Native.POINTER_SIZE == 8) {
+            assertEquals("64-bit", jvmVersion.getUsingNativeClass());
+        } else if (com.sun.jna.Native.POINTER_SIZE == 4) {
+            assertEquals("32-bit", jvmVersion.getUsingNativeClass());
+        }
+    }
+
+    @Test
+    public void whenUsingPlatformClass_thenResultIsAsExpected() {
+        if (Platform.is64Bit() == Boolean.TRUE) {
+            assertEquals(Boolean.TRUE, jvmVersion.getUsingPlatformClass());
+        } else if (com.sun.jna.Native.POINTER_SIZE == 4) {
+            assertEquals(Boolean.FALSE, jvmVersion.getUsingPlatformClass());
+        }
+    }
+}