Catch LinkageError for ClassLoaderUtil.isClassPresent in case class i…

…s present but is failed to load

CHANGES.md

@@ -23,6 +23,7 @@ Apollo 2.0.0
 * [Support Java 17](https://github.com/apolloconfig/apollo/pull/4060)
 * [Optimize top navbar style](https://github.com/apolloconfig/apollo/pull/4073)
 * [Support export/import configs by apollo env](https://github.com/apolloconfig/apollo/pull/3947)
+* [Catch LinkageError for ClassLoaderUtil.isClassPresent in case class is present but is failed to load](https://github.com/apolloconfig/apollo/pull/4097)
 
 ------------------
 All issues and pull requests are [here](https://github.com/ctripcorp/apollo/milestone/8?closed=1)

apollo-core/src/main/java/com/ctrip/framework/apollo/core/utils/ClassLoaderUtil.java

@@ -61,7 +61,6 @@ public static ClassLoader getLoader() {
     return loader;
   }
 
-
   public static String getClassPath() {
     return classPath;
   }
@@ -71,6 +70,11 @@ public static boolean isClassPresent(String className) {
       Class.forName(className);
       return true;
     } catch (ClassNotFoundException ex) {
+      // ignore expected exception
+      return false;
+    } catch (LinkageError ex) {
+      // unexpected error, need to let the user know the actual error
+      logger.error("Failed to load class: {}", className, ex);
       return false;
     }
   }

apollo-core/src/test/java/com/ctrip/framework/apollo/core/utils/ClassLoaderUtilTest.java

@@ -0,0 +1,37 @@
+package com.ctrip.framework.apollo.core.utils;
+
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+
+public class ClassLoaderUtilTest {
+  private static boolean shouldFailInInitialization = false;
+  @Test
+  public void testGetClassLoader() {
+    assertNotNull(ClassLoaderUtil.getLoader());
+  }
+
+  @Test
+  public void testIsClassPresent() {
+    assertTrue(ClassLoaderUtil.isClassPresent("java.lang.String"));
+  }
+
+  @Test
+  public void testIsClassPresentWithClassNotFound() {
+    assertFalse(ClassLoaderUtil.isClassPresent("java.lang.StringNotFound"));
+  }
+
+  @Test
+  public void testIsClassPresentWithLinkageError() {
+    shouldFailInInitialization = true;
+    assertFalse(ClassLoaderUtil.isClassPresent(ClassWithInitializationError.class.getName()));
+  }
+
+  public static class ClassWithInitializationError {
+    static {
+      if (ClassLoaderUtilTest.shouldFailInInitialization) {
+        throw new RuntimeException("Some initialization exception");
+      }
+    }
+  }
+}