[jspwiki] 03/14: added utility method to check if a class is present in classpath

[juanpablo]

This is an automated email from the ASF dual-hosted git repository.

juanpablo pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/jspwiki.git

commit 7765bb242593344a310a92d0c03c3298e928d5e5
Author: juanpablo <juanpa...@apache.org>
AuthorDate: Tue Mar 31 19:15:12 2020 +0200

    added utility method to check if a class is present in classpath
---
 .../main/java/org/apache/wiki/util/ClassUtil.java  | 15 ++++++++
 .../java/org/apache/wiki/util/ClassUtilTest.java   | 45 +++++++++-------------
 2 files changed, 34 insertions(+), 26 deletions(-)

diff --git a/jspwiki-util/src/main/java/org/apache/wiki/util/ClassUtil.java 
b/jspwiki-util/src/main/java/org/apache/wiki/util/ClassUtil.java
index 8fe90e2..8da9f83 100644
--- a/jspwiki-util/src/main/java/org/apache/wiki/util/ClassUtil.java
+++ b/jspwiki-util/src/main/java/org/apache/wiki/util/ClassUtil.java
@@ -349,6 +349,21 @@ public final class ClassUtil {
         return false;
     }
 
+    /**
+     * Checks if a given class exists in classpath.
+     *
+     * @param className the class to check for existence.
+     * @return {@code true} if it exists, {@code false} otherwise.
+     */
+    public static boolean exists( final String className ) {
+        try {
+            Class.forName( className, false, ClassUtil.class.getClassLoader() 
);
+            return true;
+        } catch( final ClassNotFoundException e ) {
+            return false;
+        }
+    }
+
     public static Map< String, String > getExtraClassMappings() {
         return c_classMappingsExtra;
     }
diff --git a/jspwiki-util/src/test/java/org/apache/wiki/util/ClassUtilTest.java 
b/jspwiki-util/src/test/java/org/apache/wiki/util/ClassUtilTest.java
index 9415647..6104b43 100644
--- a/jspwiki-util/src/test/java/org/apache/wiki/util/ClassUtilTest.java
+++ b/jspwiki-util/src/test/java/org/apache/wiki/util/ClassUtilTest.java
@@ -19,11 +19,11 @@
 
 package org.apache.wiki.util;
 
-import java.util.List;
-
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import java.util.List;
+
 
 public class ClassUtilTest
 {
@@ -32,33 +32,30 @@ public class ClassUtilTest
      * tests various kinds of searches on classpath items
      */
     @Test
-    public void testClasspathSearch() throws Exception
-    {
-        List< String > jarSearch = ClassUtil.classpathEntriesUnder( "META-INF" 
);
+    public void testClasspathSearch() {
+        final List< String > jarSearch = ClassUtil.classpathEntriesUnder( 
"META-INF" );
         Assertions.assertNotNull( jarSearch );
         Assertions.assertTrue( jarSearch.size() > 0 );
 
-        List< String > fileSearch = ClassUtil.classpathEntriesUnder( 
"templates" );
+        final List< String > fileSearch = ClassUtil.classpathEntriesUnder( 
"templates" );
         Assertions.assertNotNull( fileSearch );
         Assertions.assertTrue( fileSearch.size() > 0 );
 
-        List< String > nullSearch = ClassUtil.classpathEntriesUnder( "blurb" );
+        final List< String > nullSearch = ClassUtil.classpathEntriesUnder( 
"blurb" );
         Assertions.assertNotNull( nullSearch );
-        Assertions.assertTrue( nullSearch.size() == 0 );
+        Assertions.assertEquals( 0, nullSearch.size() );
 
-        List< String > nullInputSearch = ClassUtil.classpathEntriesUnder( null 
);
+        final List< String > nullInputSearch = 
ClassUtil.classpathEntriesUnder( null );
         Assertions.assertNotNull( nullInputSearch );
-        Assertions.assertTrue( nullSearch.size() == 0 );
+        Assertions.assertEquals( 0, nullSearch.size() );
     }
 
     /**
      *  Tries to find an existing class.
      */
     @Test
-    public void testFindClass()
-        throws Exception
-    {
-        Class< ? > foo = ClassUtil.findClass( "java.util", "List" );
+    public void testFindClass() throws Exception {
+        final Class< ? > foo = ClassUtil.findClass( "java.util", "List" );
 
         Assertions.assertEquals( foo.getName(), "java.util.List" );
     }
@@ -67,18 +64,8 @@ public class ClassUtilTest
      *  Non-existant classes should throw ClassNotFoundEx.
      */
     @Test
-    public void testFindClassNoClass()
-        throws Exception
-    {
-        try
-        {
-            Class< ? > foo = ClassUtil.findClass( "org.apache.wiki", 
"MubbleBubble" );
-            Assertions.fail( "Found class:" + foo );
-        }
-        catch( ClassNotFoundException e )
-        {
-            // Expected
-        }
+    public void testFindClassNoClass() {
+        Assertions.assertThrows( ClassNotFoundException.class, () ->  
ClassUtil.findClass( "org.apache.wiki", "MubbleBubble" ) );
     }
 
     @Test
@@ -90,4 +77,10 @@ public class ClassUtilTest
         Assertions.assertFalse( ClassUtil.assignable( "java.util.List", 
"java.util.HashMap" ) );
     }
 
+    @Test
+    public void testExists() {
+        Assertions.assertTrue( ClassUtil.exists( "java.util.List" ) );
+        Assertions.assertFalse( ClassUtil.exists( "org.apache.wiski.FrisFrus" 
) );
+    }
+
 }