Fix quality flaw: Returns empty arrays instead of null

Author: Wohops

java-squid/src/main/java/org/sonar/java/bytecode/loader/FileSystemLoader.java

@@ -62,14 +62,14 @@ public byte[] loadBytes(String name) {
     }
     File file = new File(baseDir, name);
     if (!file.exists()) {
-      return null;
+      return new byte[0];
     }
     InputStream is = null;
     try {
       is = new FileInputStream(file);
       return IOUtils.toByteArray(is);
     } catch (IOException e) {
-      return null;
+      return new byte[0];
     } finally {
       IOUtils.closeQuietly(is);
     }

java-squid/src/main/java/org/sonar/java/bytecode/loader/JarLoader.java

@@ -70,14 +70,14 @@ public byte[] loadBytes(String name) {
     try {
       ZipEntry entry = jarFile.getEntry(name);
       if (entry == null) {
-        return null;
+        return new byte[0];
       }
       is = jarFile.getInputStream(entry);
       return IOUtils.toByteArray(is);
     } catch (IOException e) {
       // TODO Godin: not sure that we should silently ignore exception here,
       // e.g. it can be thrown if file corrupted
-      return null;
+      return new byte[0];
     } finally {
       IOUtils.closeQuietly(is);
     }

java-squid/src/main/java/org/sonar/java/bytecode/loader/SquidClassLoader.java

@@ -20,6 +20,7 @@
 package org.sonar.java.bytecode.loader;
 
 import com.google.common.collect.Iterators;
+import org.apache.commons.lang.ArrayUtils;
 
 import java.io.Closeable;
 import java.io.File;
@@ -58,7 +59,7 @@ protected Class findClass(String name) throws ClassNotFoundException {
     String resourceName = name.replace('.', '/') + ".class";
     for (Loader loader : loaders) {
       byte[] classBytes = loader.loadBytes(resourceName);
-      if (classBytes != null) {
+      if (ArrayUtils.isNotEmpty(classBytes)) {
         // TODO Godin: definePackage ?
         return defineClass(name, classBytes, 0, classBytes.length);
       }

java-squid/src/test/java/org/sonar/java/bytecode/loader/FileSystemLoaderTest.java

@@ -66,9 +66,9 @@ public void testLoadBytes() throws Exception {
     File dir = new File("src/test/files/bytecode/bin/");
     FileSystemLoader loader = new FileSystemLoader(dir);
 
-    assertThat(loader.loadBytes("notfound")).isNull();
+    assertThat(loader.loadBytes("notfound")).isEmpty();
 
-    assertThat(loader.loadBytes("tags/TagName.class")).isNotNull();
+    assertThat(loader.loadBytes("tags/TagName.class")).isNotEmpty();
 
     loader.close();
 

java-squid/src/test/java/org/sonar/java/bytecode/loader/JarLoaderTest.java

@@ -74,10 +74,10 @@ public void testLoadBytes() throws Exception {
     File jar = new File("src/test/files/bytecode/lib/hello.jar");
     JarLoader loader = new JarLoader(jar);
 
-    assertThat(loader.loadBytes("notfound")).isNull();
+    assertThat(loader.loadBytes("notfound")).isEmpty();
 
     byte[] bytes = loader.loadBytes("META-INF/MANIFEST.MF");
-    assertThat(bytes).isNotNull();
+    assertThat(bytes).isNotEmpty();
     ByteArrayInputStream is = new ByteArrayInputStream(bytes);
     assertThat(IOUtils.readLines(is)).contains("Manifest-Version: 1.0");