Map<String, Object> parentMap = new HashMap<>();
        DocMap docMap = new DocMap(parentMap);

        assertNull(docMap.put("newKey", "newValue"));
        assertEquals("newValue", docMap.get("newKey"));

        assertEquals("newValue", docMap.put("newKey", "updatedValue"));
        assertEquals("updatedValue", docMap.get("newKey"));

        assertNull(docMap.get("nonexistent"));
    }

    @Test

        TestFessTransformer transformer = new TestFessTransformer();
        Map<String, Object> dataMap = new HashMap<>();

        transformer.putResultDataBody(dataMap, "newKey", "newValue");

        assertEquals("newValue", dataMap.get("newKey"));
        assertEquals(1, dataMap.size());
    }

    /**
     * Test putResultDataBody with null handling
     */
    @Test

            @Override
            public Object evaluate(String template, Map<String, Object> paramMap) {
                // Try to add new param
                paramMap.put("newKey", "newValue");
                return paramMap.size();
            }
        });

        // Execute first time
        Object result1 = scriptExecutor.execute("modifyEngine", "script1");

        // Test overwriting existing keys
        paramMap = new HashMap<>();
        paramMap.put("key1", "oldValue");
        configParam = "key1=newValue";
        ParameterUtil.loadConfigParams(paramMap, configParam);
        assertEquals(1, paramMap.size());
        assertEquals("newValue", paramMap.get("key1"));
    }

    @Test
    public void test_createConfigParameterMap() {
        String configParameters;