From 90353ceb79f5dd132e7e73df31e11df56c120bec Mon Sep 17 00:00:00 2001
From: Alexander Reelsen <alexander@reelsen.net>
Date: Thu, 25 Apr 2013 15:13:31 +0200
Subject: [PATCH] Fixing possible NoClassDefFoundError when trying to load
 nonexisting classes

In order to handle exceptions correctly, when classes are not found, one
needs to handle ClassNotFoundException as well as NoClassDefFoundError
in order to be sure to have caught every possible case. We did not cater
for the latter in ImmutableSettings yet.

This fix is just executing the same logic for both exceptions instead of
simply bubbling up NoClassDefFoundError.
---
 .../common/settings/ImmutableSettings.java     | 18 ++++++++++++------
 .../settings/ImmutableSettingsTests.java       |  6 ++++++
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/main/java/org/elasticsearch/common/settings/ImmutableSettings.java b/src/main/java/org/elasticsearch/common/settings/ImmutableSettings.java
index 4021c4219a3..4f2fb4831f2 100644
--- a/src/main/java/org/elasticsearch/common/settings/ImmutableSettings.java
+++ b/src/main/java/org/elasticsearch/common/settings/ImmutableSettings.java
@@ -332,16 +332,22 @@ public class ImmutableSettings implements Settings {
             try {
                 return (Class<? extends T>) getClassLoader().loadClass(fullClassName);
             } catch (ClassNotFoundException e1) {
-                fullClassName = prefixValue + toCamelCase(sValue).toLowerCase() + "." + Strings.capitalize(toCamelCase(sValue)) + suffixClassName;
-                try {
-                    return (Class<? extends T>) getClassLoader().loadClass(fullClassName);
-                } catch (ClassNotFoundException e2) {
-                    throw new NoClassSettingsException("Failed to load class setting [" + setting + "] with value [" + get(setting) + "]", e2);
-                }
+                return loadClass(prefixValue, sValue, suffixClassName, setting);
+            } catch (NoClassDefFoundError e1) {
+                return loadClass(prefixValue, sValue, suffixClassName, setting);
             }
         }
     }
 
+    private <T> Class<? extends T> loadClass(String prefixValue, String sValue, String suffixClassName, String setting) {
+        String fullClassName = prefixValue + toCamelCase(sValue).toLowerCase() + "." + Strings.capitalize(toCamelCase(sValue)) + suffixClassName;
+        try {
+            return (Class<? extends T>) getClassLoader().loadClass(fullClassName);
+        } catch (ClassNotFoundException e2) {
+            throw new NoClassSettingsException("Failed to load class setting [" + setting + "] with value [" + get(setting) + "]", e2);
+        }
+    }
+
     @Override
     public String[] getAsArray(String settingPrefix) throws SettingsException {
         return getAsArray(settingPrefix, Strings.EMPTY_ARRAY);
diff --git a/src/test/java/org/elasticsearch/test/unit/common/settings/ImmutableSettingsTests.java b/src/test/java/org/elasticsearch/test/unit/common/settings/ImmutableSettingsTests.java
index 417817fec43..b1fd9fda5ae 100644
--- a/src/test/java/org/elasticsearch/test/unit/common/settings/ImmutableSettingsTests.java
+++ b/src/test/java/org/elasticsearch/test/unit/common/settings/ImmutableSettingsTests.java
@@ -81,4 +81,10 @@ public class ImmutableSettingsTests {
         assertThat(settings.toDelimitedString(';'), equalTo("key1=value1;key2=value2;"));
     }
 
+    @Test(expectedExceptions = NoClassSettingsException.class)
+    public void testThatAllClassNotFoundExceptionsAreCaught() {
+        // this should be nGram in order to really work, but for sure not not throw a NoClassDefFoundError
+        Settings settings = settingsBuilder().put("type", "ngram").build();
+        settings.getAsClass("type", null, "org.elasticsearch.index.analysis.", "TokenFilterFactory");
+    }
 }