issue_541: Added a check and tests for empty string and null string json object (#553)

* Added a check and tests for empty string and null string properties so that fromjson() does translate and return a null

* Update src/main/java/com/teragrep/pth10/steps/teragrep/bloomfilter/FilterTypes.java

Co-authored-by: elliVM <[email protected]>

* set helper methods to private and run spotless

---------

Co-authored-by: elliVM <[email protected]>

Author: Abigael-JT

src/main/java/com/teragrep/pth_10/steps/teragrep/bloomfilter/FilterTypes.java

@@ -123,7 +123,7 @@ private String sizesJsonString() {
         final String BLOOM_NUMBER_OF_FIELDS_CONFIG_ITEM = "dpl.pth_06.bloom.db.fields";
         if (config.hasPath(BLOOM_NUMBER_OF_FIELDS_CONFIG_ITEM)) {
             jsonString = config.getString(BLOOM_NUMBER_OF_FIELDS_CONFIG_ITEM);
-            if (jsonString == null || jsonString.isEmpty()) {
+            if (jsonString == null || jsonString.isEmpty() || "null".equals(jsonString)) {
                 throw new RuntimeException("Bloom filter size fields was not configured.");
             }
         }

src/test/java/com/teragrep/pth_10/steps/teragrep/bloomfilter/FilterTypesTest.java

@@ -105,6 +105,26 @@ public void testSortedMapMethod() {
 
     }
 
+    @Test
+    public void testSortedMapMethodWithEmptyStringJSON() {
+        Config config = ConfigFactory.parseProperties(emptyStringProperties());
+        FilterTypes filterTypes = new FilterTypes(config);
+        Exception exception = assertThrows(RuntimeException.class, () -> {
+            filterTypes.sortedMap();
+        });
+        Assertions.assertEquals("Bloom filter size fields was not configured.", exception.getMessage());
+    }
+
+    @Test
+    public void testSortedMapMethodWithNullStringJSON() {
+        Config config = ConfigFactory.parseProperties(nullStringProperties());
+        FilterTypes filterTypes = new FilterTypes(config);
+        Exception exception = assertThrows(RuntimeException.class, () -> {
+            filterTypes.sortedMap();
+        });
+        Assertions.assertEquals("Bloom filter size fields was not configured.", exception.getMessage());
+    }
+
     @Test
     public void testBitSizeMapMethod() {
         Config config = ConfigFactory.parseProperties(defaultProperties());
@@ -209,7 +229,7 @@ public void testEqualsVerifier() {
         EqualsVerifier.forClass(FilterTypes.class).withNonnullFields("config").verify();
     }
 
-    public Properties defaultProperties() {
+    private Properties defaultProperties() {
         Properties properties = new Properties();
         properties.put("dpl.pth_10.bloom.db.username", username);
         properties.put("dpl.pth_10.bloom.db.password", password);
@@ -222,4 +242,22 @@ public Properties defaultProperties() {
                 );
         return properties;
     }
+
+    private Properties emptyStringProperties() {
+        Properties properties = new Properties();
+        properties.put("dpl.pth_10.bloom.db.username", username);
+        properties.put("dpl.pth_10.bloom.db.password", password);
+        properties.put("dpl.pth_06.bloom.db.url", connectionUrl);
+        properties.put("dpl.pth_06.bloom.db.fields", "");
+        return properties;
+    }
+
+    private Properties nullStringProperties() {
+        Properties properties = new Properties();
+        properties.put("dpl.pth_10.bloom.db.username", username);
+        properties.put("dpl.pth_10.bloom.db.password", password);
+        properties.put("dpl.pth_06.bloom.db.url", connectionUrl);
+        properties.put("dpl.pth_06.bloom.db.fields", "null");
+        return properties;
+    }
 }