diff --git a/JSON/include/Poco/JSON/Array.h b/JSON/include/Poco/JSON/Array.h
index 1e0c9e6432..dca8692208 100644
--- a/JSON/include/Poco/JSON/Array.h
+++ b/JSON/include/Poco/JSON/Array.h
@@ -217,7 +217,7 @@ class JSON_API Array
 private:
 	void resetDynArray() const;
 
-	typedef SharedPtr<Poco::Dynamic::Array> ArrayPtr;
+	using ArrayPtr = SharedPtr<Poco::Dynamic::Array>;
 
 	ValueVec         _values;
 	mutable ArrayPtr _pArray;
@@ -340,98 +340,96 @@ class VarHolderImpl<JSON::Array::Ptr>: public VarHolder
 	{
 	}
 
-	~VarHolderImpl()
-	{
-	}
+	~VarHolderImpl() override = default;
 
-	const std::type_info& type() const
+	const std::type_info& type() const override
 	{
 		return typeid(JSON::Array::Ptr);
 	}
 
-	void convert(Int8&) const
+	void convert(Int8&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int16&) const
+	void convert(Int16&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int32&) const
+	void convert(Int32&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int64&) const
+	void convert(Int64&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt8&) const
+	void convert(UInt8&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt16&) const
+	void convert(UInt16&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt32&) const
+	void convert(UInt32&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt64&) const
+	void convert(UInt64&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(bool& value) const
+	void convert(bool& value) const override
 	{
 		value = !_val.isNull() && _val->size() > 0;
 	}
 
-	void convert(float&) const
+	void convert(float&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(double&) const
+	void convert(double&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(char&) const
+	void convert(char&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(std::string& s) const
+	void convert(std::string& s) const override
 	{
 		std::ostringstream oss;
 		_val->stringify(oss);
 		s = oss.str();
 	}
 
-	void convert(DateTime& /*val*/) const
+	void convert(DateTime& /*val*/) const override
 	{
 		throw BadCastException("Cannot convert Array to DateTime");
 	}
 
-	void convert(LocalDateTime& /*ldt*/) const
+	void convert(LocalDateTime& /*ldt*/) const override
 	{
 		throw BadCastException("Cannot convert Array to LocalDateTime");
 	}
 
-	void convert(Timestamp& /*ts*/) const
+	void convert(Timestamp& /*ts*/) const override
 	{
 		throw BadCastException("Cannot convert Array to Timestamp");
 	}
 
-	VarHolder* clone(Placeholder<VarHolder>* pVarHolder = 0) const
+	VarHolder* clone(Placeholder<VarHolder>* pVarHolder = nullptr) const override
 	{
 		return cloneHolder(pVarHolder, _val);
 	}
@@ -441,22 +439,22 @@ class VarHolderImpl<JSON::Array::Ptr>: public VarHolder
 		return _val;
 	}
 
-	bool isInteger() const
+	bool isInteger() const override
 	{
 		return false;
 	}
 
-	bool isSigned() const
+	bool isSigned() const override
 	{
 		return false;
 	}
 
-	bool isNumeric() const
+	bool isNumeric() const override
 	{
 		return false;
 	}
 
-	bool isString() const
+	bool isString() const override
 	{
 		return false;
 	}
@@ -474,98 +472,96 @@ class VarHolderImpl<JSON::Array>: public VarHolder
 	{
 	}
 
-	~VarHolderImpl()
-	{
-	}
+	~VarHolderImpl() override = default;
 
-	const std::type_info& type() const
+	const std::type_info& type() const override
 	{
 		return typeid(JSON::Array);
 	}
 
-	void convert(Int8&) const
+	void convert(Int8&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int16&) const
+	void convert(Int16&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int32&) const
+	void convert(Int32&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int64&) const
+	void convert(Int64&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt8&) const
+	void convert(UInt8&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt16&) const
+	void convert(UInt16&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt32&) const
+	void convert(UInt32&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt64&) const
+	void convert(UInt64&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(bool& value) const
+	void convert(bool& value) const override
 	{
 		value = _val.size() > 0;
 	}
 
-	void convert(float&) const
+	void convert(float&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(double&) const
+	void convert(double&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(char&) const
+	void convert(char&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(std::string& s) const
+	void convert(std::string& s) const override
 	{
 		std::ostringstream oss;
 		_val.stringify(oss);
 		s = oss.str();
 	}
 
-	void convert(DateTime& /*val*/) const
+	void convert(DateTime& /*val*/) const override
 	{
 		throw BadCastException("Cannot convert Array to DateTime");
 	}
 
-	void convert(LocalDateTime& /*ldt*/) const
+	void convert(LocalDateTime& /*ldt*/) const override
 	{
 		throw BadCastException("Cannot convert Array to LocalDateTime");
 	}
 
-	void convert(Timestamp& /*ts*/) const
+	void convert(Timestamp& /*ts*/) const override
 	{
 		throw BadCastException("Cannot convert Array to Timestamp");
 	}
 
-	VarHolder* clone(Placeholder<VarHolder>* pVarHolder = 0) const
+	VarHolder* clone(Placeholder<VarHolder>* pVarHolder = nullptr) const override
 	{
 		return cloneHolder(pVarHolder, _val);
 	}
@@ -575,22 +571,22 @@ class VarHolderImpl<JSON::Array>: public VarHolder
 		return _val;
 	}
 
-	bool isInteger() const
+	bool isInteger() const override
 	{
 		return false;
 	}
 
-	bool isSigned() const
+	bool isSigned() const override
 	{
 		return false;
 	}
 
-	bool isNumeric() const
+	bool isNumeric() const override
 	{
 		return false;
 	}
 
-	bool isString() const
+	bool isString() const override
 	{
 		return false;
 	}
diff --git a/JSON/include/Poco/JSON/Object.h b/JSON/include/Poco/JSON/Object.h
index 5a9585b3b1..2efd4465dc 100644
--- a/JSON/include/Poco/JSON/Object.h
+++ b/JSON/include/Poco/JSON/Object.h
@@ -188,7 +188,7 @@ class JSON_API Object
 	bool isArray(const std::string& key) const;
 		/// Returns true when the given property contains an array.
 
-	bool isArray(ConstIterator& it) const;
+	bool isArray(const ConstIterator& it) const;
 		/// Returns true when the given property contains an array.
 
 	bool isNull(const std::string& key) const;
@@ -197,7 +197,7 @@ class JSON_API Object
 	bool isObject(const std::string& key) const;
 		/// Returns true when the given property contains an object.
 
-	bool isObject(ConstIterator& it) const;
+	bool isObject(const ConstIterator& it) const;
 		/// Returns true when the given property contains an object.
 
 	template<typename T>
@@ -207,7 +207,7 @@ class JSON_API Object
 		/// def will be returned.
 	{
 		T value = def;
-		ValueMap::const_iterator it = _values.find(key);
+		auto it = _values.find(key);
 		if (it != _values.end() && ! it->second.isEmpty())
 		{
 			try
@@ -255,9 +255,9 @@ class JSON_API Object
 		/// Insertion order preservation property is left intact.
 
 private:
-	typedef std::deque<ValueMap::const_iterator>  KeyList;
-	typedef Poco::DynamicStruct::Ptr              StructPtr;
-	typedef Poco::OrderedDynamicStruct::Ptr       OrdStructPtr;
+	using KeyList = std::deque<ValueMap::const_iterator>;
+	using StructPtr = Poco::DynamicStruct::Ptr;
+	using OrdStructPtr = Poco::OrderedDynamicStruct::Ptr;
 
 	void syncKeys(const KeyList& keys);
 
@@ -311,30 +311,28 @@ class JSON_API Object
 
 		if (obj->_preserveInsOrder)
 		{
-			KeyList::const_iterator it = obj->_keys.begin();
-			KeyList::const_iterator end = obj->_keys.end();
-			for (; it != end; ++it)
+			for (const auto& it: obj->_keys)
 			{
-				if (obj->isObject((*it)->first))
+				if (obj->isObject(it->first))
 				{
-					Object::Ptr pObj = obj->getObject((*it)->first);
+					Object::Ptr pObj = obj->getObject(it->first);
 					S str = makeStructImpl<S>(pObj);
-					ds.insert((*it)->first, str);
+					ds.insert(it->first, str);
 				}
-				else if (obj->isArray((*it)->first))
+				else if (obj->isArray(it->first))
 				{
-					Array::Ptr pArr = obj->getArray((*it)->first);
+					Array::Ptr pArr = obj->getArray(it->first);
 					std::vector<Poco::Dynamic::Var> v = Poco::JSON::Array::makeArray(pArr);
-					ds.insert((*it)->first, v);
+					ds.insert(it->first, v);
 				}
 				else
-					ds.insert((*it)->first, (*it)->second);
+					ds.insert(it->first, it->second);
 			}
 		}
 		else
 		{
-			ConstIterator it = obj->begin();
-			ConstIterator end = obj->end();
+			auto it = obj->begin();
+			const auto end = obj->end();
 			for (; it != end; ++it)
 			{
 				if (obj->isObject(it))
@@ -430,19 +428,19 @@ inline Object::ConstIterator Object::end() const
 
 inline bool Object::has(const std::string& key) const
 {
-	ValueMap::const_iterator it = _values.find(key);
+	const auto it = _values.find(key);
 	return it != _values.end();
 }
 
 
 inline bool Object::isArray(const std::string& key) const
 {
-	ValueMap::const_iterator it = _values.find(key);
+	const auto it = _values.find(key);
 	return isArray(it);
 }
 
 
-inline bool Object::isArray(ConstIterator& it) const
+inline bool Object::isArray(const ConstIterator& it) const
 {
 	return it != _values.end() && (it->second.type() == typeid(Array::Ptr) || it->second.type() == typeid(Array));
 }
@@ -450,19 +448,19 @@ inline bool Object::isArray(ConstIterator& it) const
 
 inline bool Object::isNull(const std::string& key) const
 {
-	ValueMap::const_iterator it = _values.find(key);
+	const auto it = _values.find(key);
 	return it == _values.end() || it->second.isEmpty();
 }
 
 
 inline bool Object::isObject(const std::string& key) const
 {
-	ValueMap::const_iterator it = _values.find(key);
+	const auto it = _values.find(key);
 	return isObject(it);
 }
 
 
-inline bool Object::isObject(ConstIterator& it) const
+inline bool Object::isObject(const ConstIterator& it) const
 {
 	return it != _values.end() && (it->second.type() == typeid(Object::Ptr) || it->second.type() == typeid(Object));
 }
@@ -478,8 +476,8 @@ inline void Object::remove(const std::string& key)
 {
 	if (_preserveInsOrder)
 	{
-		KeyList::iterator it = _keys.begin();
-		KeyList::iterator end = _keys.end();
+		auto it = _keys.begin();
+		const auto end = _keys.end();
 		for (; it != end; ++it)
 		{
 			if (key == (*it)->first)
@@ -508,7 +506,7 @@ inline const Dynamic::Var& Object::getValue(ValueMap::const_iterator& it) const
 
 inline const Dynamic::Var& Object::getValue(KeyList::const_iterator& it) const
 {
-	ValueMap::const_iterator itv = _values.find((*it)->first);
+	const auto itv = _values.find((*it)->first);
 	if (itv != _values.end())
 		return itv->second;
 	else
@@ -531,101 +529,99 @@ class VarHolderImpl<JSON::Object::Ptr>: public VarHolder
 	{
 	}
 
-	~VarHolderImpl()
-	{
-	}
+	~VarHolderImpl() override = default;
 
-	const std::type_info& type() const
+	const std::type_info& type() const override
 	{
 		return typeid(JSON::Object::Ptr);
 	}
 
-	void convert(Int8&) const
+	void convert(Int8&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int16&) const
+	void convert(Int16&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int32&) const
+	void convert(Int32&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int64&) const
+	void convert(Int64&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt8&) const
+	void convert(UInt8&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt16&) const
+	void convert(UInt16&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt32&) const
+	void convert(UInt32&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt64&) const
+	void convert(UInt64&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(bool& value) const
+	void convert(bool& value) const override
 	{
 		value = !_val.isNull() && _val->size() > 0;
 	}
 
-	void convert(float&) const
+	void convert(float&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(double&) const
+	void convert(double&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(char&) const
+	void convert(char&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(std::string& s) const
+	void convert(std::string& s) const override
 	{
 		std::ostringstream oss;
 		_val->stringify(oss);
 		s = oss.str();
 	}
 
-	void convert(DateTime& /*val*/) const
+	void convert(DateTime& /*val*/) const override
 	{
 		//TODO: val = _val;
 		throw NotImplementedException("Conversion not implemented: JSON:Object => DateTime");
 	}
 
-	void convert(LocalDateTime& /*ldt*/) const
+	void convert(LocalDateTime& /*ldt*/) const override
 	{
 		//TODO: ldt = _val.timestamp();
 		throw NotImplementedException("Conversion not implemented: JSON:Object => LocalDateTime");
 	}
 
-	void convert(Timestamp& /*ts*/) const
+	void convert(Timestamp& /*ts*/) const override
 	{
 		//TODO: ts = _val.timestamp();
 		throw NotImplementedException("Conversion not implemented: JSON:Object => Timestamp");
 	}
 
-	VarHolder* clone(Placeholder<VarHolder>* pVarHolder = 0) const
+	VarHolder* clone(Placeholder<VarHolder>* pVarHolder = nullptr) const override
 	{
 		return cloneHolder(pVarHolder, _val);
 	}
@@ -635,27 +631,27 @@ class VarHolderImpl<JSON::Object::Ptr>: public VarHolder
 		return _val;
 	}
 
-	bool isArray() const
+	bool isArray() const override
 	{
 		return false;
 	}
 
-	bool isInteger() const
+	bool isInteger() const override
 	{
 		return false;
 	}
 
-	bool isSigned() const
+	bool isSigned() const override
 	{
 		return false;
 	}
 
-	bool isNumeric() const
+	bool isNumeric() const override
 	{
 		return false;
 	}
 
-	bool isString() const
+	bool isString() const override
 	{
 		return false;
 	}
@@ -673,101 +669,99 @@ class VarHolderImpl<JSON::Object>: public VarHolder
 	{
 	}
 
-	~VarHolderImpl()
-	{
-	}
+	~VarHolderImpl() override = default;
 
-	const std::type_info& type() const
+	const std::type_info& type() const override
 	{
 		return typeid(JSON::Object);
 	}
 
-	void convert(Int8&) const
+	void convert(Int8&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int16&) const
+	void convert(Int16&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int32&) const
+	void convert(Int32&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(Int64&) const
+	void convert(Int64&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt8&) const
+	void convert(UInt8&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt16&) const
+	void convert(UInt16&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt32&) const
+	void convert(UInt32&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(UInt64&) const
+	void convert(UInt64&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(bool& value) const
+	void convert(bool& value) const override
 	{
 		value = _val.size() > 0;
 	}
 
-	void convert(float&) const
+	void convert(float&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(double&) const
+	void convert(double&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(char&) const
+	void convert(char&) const override
 	{
 		throw BadCastException();
 	}
 
-	void convert(std::string& s) const
+	void convert(std::string& s) const override
 	{
 		std::ostringstream oss;
 		_val.stringify(oss);
 		s = oss.str();
 	}
 
-	void convert(DateTime& /*val*/) const
+	void convert(DateTime& /*val*/) const override
 	{
 		//TODO: val = _val;
 		throw NotImplementedException("Conversion not implemented: JSON:Object => DateTime");
 	}
 
-	void convert(LocalDateTime& /*ldt*/) const
+	void convert(LocalDateTime& /*ldt*/) const override
 	{
 		//TODO: ldt = _val.timestamp();
 		throw NotImplementedException("Conversion not implemented: JSON:Object => LocalDateTime");
 	}
 
-	void convert(Timestamp& /*ts*/) const
+	void convert(Timestamp& /*ts*/) const override
 	{
 		//TODO: ts = _val.timestamp();
 		throw NotImplementedException("Conversion not implemented: JSON:Object => Timestamp");
 	}
 
-	VarHolder* clone(Placeholder<VarHolder>* pVarHolder = 0) const
+	VarHolder* clone(Placeholder<VarHolder>* pVarHolder = nullptr) const override
 	{
 		return cloneHolder(pVarHolder, _val);
 	}
@@ -777,27 +771,27 @@ class VarHolderImpl<JSON::Object>: public VarHolder
 		return _val;
 	}
 
-	bool isArray() const
+	bool isArray() const override
 	{
 		return false;
 	}
 
-	bool isInteger() const
+	bool isInteger() const override
 	{
 		return false;
 	}
 
-	bool isSigned() const
+	bool isSigned() const override
 	{
 		return false;
 	}
 
-	bool isNumeric() const
+	bool isNumeric() const override
 	{
 		return false;
 	}
 
-	bool isString() const
+	bool isString() const override
 	{
 		return false;
 	}
diff --git a/JSON/include/Poco/JSON/ParseHandler.h b/JSON/include/Poco/JSON/ParseHandler.h
index 80dda16b41..74c9ba9cea 100644
--- a/JSON/include/Poco/JSON/ParseHandler.h
+++ b/JSON/include/Poco/JSON/ParseHandler.h
@@ -40,61 +40,61 @@ class JSON_API ParseHandler: public Handler
 		/// inside objects is preserved. Otherwise, items
 		/// will be sorted by keys.
 
-	virtual ~ParseHandler();
+	~ParseHandler() override;
 		/// Destroys the ParseHandler.
 
-	virtual void reset();
+	void reset() override;
 		/// Resets the handler state.
 
-	void startObject();
+	void startObject() override;
 		/// Handles a '{'; a new object is started.
 
-	void endObject();
+	void endObject() override;
 		/// Handles a '}'; the object is closed.
 
-	void startArray();
+	void startArray() override;
 		/// Handles a '['; a new array is started.
 
-	void endArray();
+	void endArray() override;
 		/// Handles a ']'; the array is closed.
 
-	void key(const std::string& k);
+	void key(const std::string& k) override;
 		/// A key is read
 
-	Dynamic::Var asVar() const;
+	Dynamic::Var asVar() const override;
 		/// Returns the result of the parser (an object or an array).
 
-	virtual void value(int v);
+	void value(int v) override;
 		/// An integer value is read
 
-	virtual void value(unsigned v);
+	void value(unsigned v) override;
 		/// An unsigned value is read. This will only be triggered if the
 		/// value cannot fit into a signed int.
 
 #if defined(POCO_HAVE_INT64)
-	virtual void value(Int64 v);
+	void value(Int64 v) override;
 		/// A 64-bit integer value is read
 
-	virtual void value(UInt64 v);
+	void value(UInt64 v) override;
 		/// An unsigned 64-bit integer value is read. This will only be
 		/// triggered if the value cannot fit into a signed 64-bit integer.
 #endif
 
-	virtual void value(const std::string& s);
+	void value(const std::string& s) override;
 		/// A string value is read.
 
-	virtual void value(double d);
+	void value(double d) override;
 		/// A double value is read.
 
-	virtual void value(bool b);
+	void value(bool b) override;
 		/// A boolean value is read.
 
-	virtual void null();
+	void null() override;
 		/// A null value is read.
 
 private:
 	void setValue(const Poco::Dynamic::Var& value);
-	typedef std::stack<Dynamic::Var> Stack;
+	using Stack = std::stack<Dynamic::Var>;
 
 	Stack        _stack;
 	std::string  _key;
diff --git a/JSON/include/Poco/JSON/Parser.h b/JSON/include/Poco/JSON/Parser.h
index 3e9707f3c3..6a175990e8 100644
--- a/JSON/include/Poco/JSON/Parser.h
+++ b/JSON/include/Poco/JSON/Parser.h
@@ -20,11 +20,7 @@
 
 #include "Poco/JSON/JSON.h"
 #include "Poco/JSON/ParserImpl.h"
-#include "Poco/JSON/Object.h"
-#include "Poco/JSON/Array.h"
 #include "Poco/JSON/ParseHandler.h"
-#include "Poco/JSON/JSONException.h"
-#include "Poco/UTF8Encoding.h"
 #include "Poco/Dynamic/Var.h"
 #include <string>
 
@@ -68,7 +64,7 @@ class JSON_API Parser: private ParserImpl
 	Parser(const Handler::Ptr& pHandler = new ParseHandler);
 		/// Creates JSON Parser, using the given Handler and buffer size.
 
-	virtual ~Parser();
+	~Parser() override;
 		/// Destroys JSON Parser.
 
 	void reset();
diff --git a/JSON/include/Poco/JSON/ParserImpl.h b/JSON/include/Poco/JSON/ParserImpl.h
index 5984b2cf6c..d9349126bb 100644
--- a/JSON/include/Poco/JSON/ParserImpl.h
+++ b/JSON/include/Poco/JSON/ParserImpl.h
@@ -19,11 +19,7 @@
 
 
 #include "Poco/JSON/JSON.h"
-#include "Poco/JSON/Object.h"
-#include "Poco/JSON/Array.h"
 #include "Poco/JSON/ParseHandler.h"
-#include "Poco/JSON/JSONException.h"
-#include "Poco/UTF8Encoding.h"
 #include "Poco/Dynamic/Var.h"
 #include <string>
 
@@ -183,7 +179,7 @@ inline Dynamic::Var ParserImpl::asVarImpl() const
 {
 	if (_pHandler) return _pHandler->asVar();
 
-	return Dynamic::Var();
+	return {};
 }
 
 
diff --git a/JSON/include/Poco/JSON/PrintHandler.h b/JSON/include/Poco/JSON/PrintHandler.h
index 18d131c0f6..2bee734bd6 100644
--- a/JSON/include/Poco/JSON/PrintHandler.h
+++ b/JSON/include/Poco/JSON/PrintHandler.h
@@ -44,56 +44,56 @@ class JSON_API PrintHandler: public Handler
 	PrintHandler(std::ostream& out, unsigned indent = 0, int options = Poco::JSON_WRAP_STRINGS);
 		/// Creates the PrintHandler.
 
-	~PrintHandler();
+	~PrintHandler() override;
 		/// Destroys the PrintHandler.
 
-	void reset();
+	void reset() override;
 		/// Resets the handler state.
 
-	void startObject();
+	void startObject() override;
 		/// The parser has read a '{'; a new object is started.
 		/// If indent is greater than zero, a newline will be appended.
 
-	void endObject();
+	void endObject() override;
 		/// The parser has read a '}'; the object is closed.
 
-	void startArray();
+	void startArray() override;
 		/// The parser has read a [; a new array will be started.
 		/// If indent is greater than zero, a newline will be appended.
 
-	void endArray();
+	void endArray() override;
 		/// The parser has read a ]; the array is closed.
 
-	void key(const std::string& k);
+	void key(const std::string& k) override;
 		/// A key of an object is read; it will be written to the output,
 		/// followed by a ':'. If indent is greater than zero, the colon
 		/// is padded by a space before and after.
 
-	void null();
+	void null() override;
 		/// A null value is read; "null" will be written to the output.
 
-	void value(int v);
+	void value(int v) override;
 		/// An integer value is read.
 
-	void value(unsigned v);
+	void value(unsigned v) override;
 		/// An unsigned value is read. This will only be triggered if the
 		/// value cannot fit into a signed int.
 
 #if defined(POCO_HAVE_INT64)
-	void value(Int64 v);
+	void value(Int64 v) override;
 		/// A 64-bit integer value is read; it will be written to the output.
 
-	void value(UInt64 v);
+	void value(UInt64 v) override;
 		/// An unsigned 64-bit integer value is read; it will be written to the output.
 #endif
 
-	void value(const std::string& value);
+	void value(const std::string& value) override;
 		/// A string value is read; it will be formatted and written to the output.
 
-	void value(double d);
+	void value(double d) override;
 		/// A double value is read; it will be written to the output.
 
-	void value(bool b);
+	void value(bool b) override;
 		/// A boolean value is read; it will be written to the output.
 
 	void comma();
diff --git a/JSON/include/Poco/JSON/TemplateCache.h b/JSON/include/Poco/JSON/TemplateCache.h
index 80a09b52a1..4fe29195f7 100644
--- a/JSON/include/Poco/JSON/TemplateCache.h
+++ b/JSON/include/Poco/JSON/TemplateCache.h
@@ -21,7 +21,6 @@
 #include "Poco/JSON/JSON.h"
 #include "Poco/JSON/Template.h"
 #include "Poco/Path.h"
-#include "Poco/SharedPtr.h"
 #include "Poco/Logger.h"
 #include <vector>
 #include <map>
diff --git a/JSON/samples/Benchmark/src/Benchmark.cpp b/JSON/samples/Benchmark/src/Benchmark.cpp
index 0725ebb779..edb7ba6741 100644
--- a/JSON/samples/Benchmark/src/Benchmark.cpp
+++ b/JSON/samples/Benchmark/src/Benchmark.cpp
@@ -11,7 +11,7 @@
 
 
 #include "Poco/JSON/Parser.h"
-#include "Poco/JSON/ParseHandler.h"
+#include "Poco/JSON/Object.h"
 #include "Poco/JSON/JSONException.h"
 #include "Poco/Environment.h"
 #include "Poco/Path.h"
@@ -20,7 +20,7 @@
 #include "Poco/StreamCopier.h"
 #include "Poco/Stopwatch.h"
 #include <iostream>
-#include <iomanip>
+#include <sstream>
 
 
 int main(int argc, char** argv)
diff --git a/JSON/src/Array.cpp b/JSON/src/Array.cpp
index 9b36e4830c..230153d275 100644
--- a/JSON/src/Array.cpp
+++ b/JSON/src/Array.cpp
@@ -42,14 +42,7 @@ Array::Array(int options):
 }
 
 
-Array::Array(const Array& other) :
-	_values(other._values),
-	_pArray(other._pArray),
-	_modified(other._modified),
-	_escapeUnicode(other._escapeUnicode),
-	_lowercaseHex(other._lowercaseHex)
-{
-}
+Array::Array(const Array& other) = default;
 
 
 Array::Array(Array&& other) noexcept:
@@ -88,9 +81,7 @@ Array& Array::operator = (Array&& other) noexcept
 }
 
 
-Array::~Array()
-{
-}
+Array::~Array() = default;
 
 
 Var Array::get(unsigned int index) const
@@ -176,7 +167,7 @@ void Array::stringify(std::ostream& out, unsigned int indent, int step) const
 
 	if (indent > 0) out << std::endl;
 
-	for (ValueVec::const_iterator it = _values.begin(); it != _values.end();)
+	for (auto it = _values.begin(); it != _values.end();)
 	{
 		for (int i = 0; i < indent; i++) out << ' ';
 
@@ -210,14 +201,14 @@ void Array::resetDynArray() const
 
 Array::operator const Poco::Dynamic::Array& () const
 {
-	if (!_values.size())
+	if (_values.empty())
 	{
 		resetDynArray();
 	}
 	else if (_modified)
 	{
-		ValueVec::const_iterator it = _values.begin();
-		ValueVec::const_iterator end = _values.end();
+		auto it = _values.begin();
+		const auto end = _values.end();
 		resetDynArray();
 		int index = 0;
 		for (; it != end; ++it, ++index)
@@ -246,8 +237,8 @@ Poco::Dynamic::Array Array::makeArray(const JSON::Array::Ptr& arr)
 {
 	Poco::Dynamic::Array vec;
 
-	JSON::Array::ConstIterator it  = arr->begin();
-	JSON::Array::ConstIterator end = arr->end();
+	auto it  = arr->begin();
+	const auto end = arr->end();
 	int index = 0;
 	for (; it != end; ++it, ++index)
 	{
@@ -274,7 +265,7 @@ Poco::Dynamic::Array Array::makeArray(const JSON::Array::Ptr& arr)
 void Array::clear()
 {
 	_values.clear();
-	_pArray = 0;
+	_pArray = nullptr;
 }
 
 
diff --git a/JSON/src/Handler.cpp b/JSON/src/Handler.cpp
index e207329ad3..0406ccf947 100644
--- a/JSON/src/Handler.cpp
+++ b/JSON/src/Handler.cpp
@@ -13,32 +13,27 @@
 
 
 #include "Poco/JSON/Handler.h"
-#include "Poco/JSON/Object.h"
 
 
 namespace Poco {
 namespace JSON {
 
 
-Handler::Handler()
-{
-}
+Handler::Handler() = default;
 
 
-Handler::~Handler()
-{
-}
+Handler::~Handler() = default;
 
 
 Dynamic::Var Handler::asVar() const
 {
-	return Dynamic::Var();
+	return {};
 }
 
 
 Poco::DynamicStruct Handler::asStruct() const
 {
-	return Poco::DynamicStruct();
+	return {};
 }
 
 
diff --git a/JSON/src/Object.cpp b/JSON/src/Object.cpp
index 57d70f9edd..d575d7dd8f 100644
--- a/JSON/src/Object.cpp
+++ b/JSON/src/Object.cpp
@@ -14,7 +14,6 @@
 
 #include "Poco/JSON/Object.h"
 #include <iostream>
-#include <sstream>
 
 
 using Poco::Dynamic::Var;
@@ -43,11 +42,12 @@ Object::Object(int options):
 }
 
 
-Object::Object(const Object& other) : _values(other._values),
+Object::Object(const Object& other) :
+	_values(other._values),
 	_preserveInsOrder(other._preserveInsOrder),
 	_escapeUnicode(other._escapeUnicode),
 	_lowercaseHex(other._lowercaseHex),
-	_pStruct(!other._modified ? other._pStruct : 0),
+	_pStruct(!other._modified ? other._pStruct : nullptr),
 	_modified(other._modified)
 {
 	syncKeys(other._keys);
@@ -67,9 +67,7 @@ Object::Object(Object&& other) noexcept:
 }
 
 
-Object::~Object()
-{
-}
+Object::~Object() = default;
 
 
 Object &Object::operator = (const Object &other)
@@ -81,7 +79,7 @@ Object &Object::operator = (const Object &other)
 		_preserveInsOrder = other._preserveInsOrder;
 		_escapeUnicode = other._escapeUnicode;
 		_lowercaseHex = other._lowercaseHex;
-		_pStruct = !other._modified ? other._pStruct : 0;
+		_pStruct = !other._modified ? other._pStruct : nullptr;
 		_modified = other._modified;
 	}
 	return *this;
@@ -108,11 +106,10 @@ void Object::syncKeys(const KeyList& keys)
 	if(_preserveInsOrder)
 	{
 		// update iterators in _keys to point to copied _values
-		for(KeyList::const_iterator it = keys.begin(); it != keys.end(); ++it)
-		{
-			ValueMap::const_iterator itv = _values.find((*it)->first);
-			poco_assert (itv != _values.end());
-			_keys.push_back(itv);
+		for (const auto& key : keys) {
+			auto itv = _values.find(key->first);
+			poco_assert(itv != _values.end());
+			_keys.emplace_back(itv);
 		}
 	}
 }
@@ -120,37 +117,37 @@ void Object::syncKeys(const KeyList& keys)
 
 Var Object::get(const std::string& key) const
 {
-	ValueMap::const_iterator it = _values.find(key);
+	auto it = _values.find(key);
 	if (it != _values.end())
 	{
 		return it->second;
 	}
 
-	return Var();
+	return {};
 }
 
 
 Array::Ptr Object::getArray(const std::string& key) const
 {
-	ValueMap::const_iterator it = _values.find(key);
+	auto it = _values.find(key);
 	if ((it != _values.end()) && (it->second.type() == typeid(Array::Ptr)))
 	{
 		return it->second.extract<Array::Ptr>();
 	}
 
-	return 0;
+	return nullptr;
 }
 
 
 Object::Ptr Object::getObject(const std::string& key) const
 {
-	ValueMap::const_iterator it = _values.find(key);
+	auto it = _values.find(key);
 	if ((it != _values.end()) && (it->second.type() == typeid(Object::Ptr)))
 	{
 		return it->second.extract<Object::Ptr>();
 	}
 
-	return 0;
+	return nullptr;
 }
 
 
@@ -159,16 +156,14 @@ void Object::getNames(NameList& names) const
 	names.clear();
 	if (_preserveInsOrder)
 	{
-		for(KeyList::const_iterator it = _keys.begin(); it != _keys.end(); ++it)
-		{
-			names.push_back((*it)->first);
+		for (const auto& _key : _keys) {
+			names.push_back(_key->first);
 		}
 	}
 	else
 	{
-		for(ValueMap::const_iterator it = _values.begin(); it != _values.end(); ++it)
-		{
-			names.push_back(it->first);
+		for (const auto& _value : _values) {
+			names.push_back(_value.first);
 		}
 	}
 }
@@ -195,8 +190,8 @@ void Object::stringify(std::ostream& out, unsigned int indent, int step) const
 
 const std::string& Object::getKey(KeyList::const_iterator& iter) const
 {
-	ValueMap::const_iterator it = _values.begin();
-	ValueMap::const_iterator end = _values.end();
+	auto it = _values.begin();
+	auto end = _values.end();
 	for (; it != end; ++it)
 	{
 		if (it == *iter) return it->first;
@@ -212,13 +207,13 @@ Object& Object::set(const std::string& key, const Dynamic::Var& value)
 	if (!ret.second) ret.first->second = value;
 	if (_preserveInsOrder)
 	{
-		KeyList::iterator it = _keys.begin();
-		KeyList::iterator end = _keys.end();
+		auto it = _keys.begin();
+		const auto end = _keys.end();
 		for (; it != end; ++it)
 		{
 			if (key == (*it)->first) return *this;
 		}
-		_keys.push_back(ret.first);
+		_keys.emplace_back(ret.first);
 	}
 	_modified = true;
 	return *this;
@@ -259,14 +254,14 @@ void Object::resetDynStruct() const
 
 Object::operator const Poco::DynamicStruct& () const
 {
-	if (!_values.size())
+	if (_values.empty())
 	{
 		resetDynStruct(_pStruct);
 	}
 	else if (_modified)
 	{
-		ValueMap::const_iterator it = _values.begin();
-		ValueMap::const_iterator end = _values.end();
+		auto it = _values.begin();
+		const auto end = _values.end();
 		resetDynStruct(_pStruct);
 		for (; it != end; ++it)
 		{
@@ -291,7 +286,7 @@ Object::operator const Poco::DynamicStruct& () const
 
 Object::operator const Poco::OrderedDynamicStruct& () const
 {
-	if (!_values.size())
+	if (_values.empty())
 	{
 		resetDynStruct(_pOrdStruct);
 	}
@@ -299,8 +294,8 @@ Object::operator const Poco::OrderedDynamicStruct& () const
 	{
 		if (_preserveInsOrder)
 		{
-			KeyList::const_iterator it = _keys.begin();
-			KeyList::const_iterator end = _keys.end();
+			auto it = _keys.begin();
+			const auto end = _keys.end();
 			resetDynStruct(_pOrdStruct);
 			for (; it != end; ++it)
 			{
@@ -320,8 +315,8 @@ Object::operator const Poco::OrderedDynamicStruct& () const
 		}
 		else
 		{
-			ValueMap::const_iterator it = _values.begin();
-			ValueMap::const_iterator end = _values.end();
+			auto it = _values.begin();
+			const auto end = _values.end();
 			resetDynStruct(_pOrdStruct);
 			for (; it != end; ++it)
 			{
@@ -349,7 +344,7 @@ void Object::clear()
 {
 	_values.clear();
 	_keys.clear();
-	_pStruct = 0;
+	_pStruct = nullptr;
 	_modified = true;
 }
 
diff --git a/JSON/src/ParseHandler.cpp b/JSON/src/ParseHandler.cpp
index 99de30c160..fdb2d995ec 100644
--- a/JSON/src/ParseHandler.cpp
+++ b/JSON/src/ParseHandler.cpp
@@ -30,9 +30,7 @@ ParseHandler::ParseHandler(bool preserveObjectOrder) : Handler(),
 }
 
 
-ParseHandler::~ParseHandler()
-{
-}
+ParseHandler::~ParseHandler() = default;
 
 
 void ParseHandler::reset()
@@ -67,7 +65,7 @@ void ParseHandler::startObject()
 		}
 	}
 
-	_stack.push(newObj);
+	_stack.emplace(newObj);
 }
 
 
@@ -102,7 +100,7 @@ void ParseHandler::startArray()
 		}
 	}
 
-	_stack.push(newArr);
+	_stack.emplace(newArr);
 }
 
 
@@ -120,7 +118,7 @@ void ParseHandler::key(const std::string& k)
 
 void ParseHandler::setValue(const Var& value)
 {
-	if (_stack.size())
+	if (!_stack.empty())
 	{
 		Var parent = _stack.top();
 
diff --git a/JSON/src/Parser.cpp b/JSON/src/Parser.cpp
index 5da4985891..1dec9e823c 100644
--- a/JSON/src/Parser.cpp
+++ b/JSON/src/Parser.cpp
@@ -13,16 +13,9 @@
 
 
 #include "Poco/JSON/Parser.h"
-#include "Poco/JSON/JSONException.h"
-#include "Poco/Ascii.h"
-#include "Poco/Token.h"
-#include "Poco/UTF8Encoding.h"
-#include "Poco/String.h"
 #undef min
 #undef max
-#include <limits>
 #include <clocale>
-#include <istream>
 
 
 namespace Poco {
@@ -35,9 +28,7 @@ Parser::Parser(const Handler::Ptr& pHandler):
 }
 
 
-Parser::~Parser()
-{
-}
+Parser::~Parser() = default;
 
 
 void Parser::setHandler(const Handler::Ptr& pHandler)
diff --git a/JSON/src/ParserImpl.cpp b/JSON/src/ParserImpl.cpp
index 4ec5b701e9..eae24f1e0d 100644
--- a/JSON/src/ParserImpl.cpp
+++ b/JSON/src/ParserImpl.cpp
@@ -11,23 +11,20 @@
 // SPDX-License-Identifier:	BSL-1.0
 //
 
+#include <Poco/JSON/ParserImpl.h>
+#include <Poco/JSON/JSONException.h>
+#include <Poco/StreamCopier.h>
 
-#include "Poco/JSON/Parser.h"
-#include "Poco/JSON/JSONException.h"
-#include "Poco/Ascii.h"
-#include "Poco/Token.h"
-#include "Poco/UTF8Encoding.h"
-#include "Poco/String.h"
-#include "Poco/StreamCopier.h"
 #undef min
 #undef max
-#include <limits>
-#include <clocale>
+
 #include <istream>
+#include <streambuf>
+#include <clocale>
 #include "pdjson.h"
 
 
-typedef struct json_stream json_stream;
+using json_stream = struct json_stream;
 
 
 namespace Poco {
@@ -38,13 +35,13 @@ extern "C"
 {
 	static int istream_get(void* ptr)
 	{
-		std::streambuf* pBuf = reinterpret_cast<std::streambuf*>(ptr);
+		auto pBuf = reinterpret_cast<std::streambuf*>(ptr);
 		return pBuf->sbumpc();
 	}
 
 	static int istream_peek(void* ptr)
 	{
-		std::streambuf* pBuf = reinterpret_cast<std::streambuf*>(ptr);
+		auto pBuf = reinterpret_cast<std::streambuf*>(ptr);
 		return pBuf->sgetc();
 	}
 }
@@ -167,8 +164,7 @@ void ParserImpl::stripComments(std::string& json)
 		std::string::iterator it = json.begin();
 		for (; it != json.end();)
 		{
-			if (*it == '"' && !inString) inString = true;
-			else inString = false;
+			inString = *it == '"' && !inString;
 			if (!inString)
 			{
 				if (*it == '/' && it + 1 != json.end() && *(it + 1) == '*')
@@ -220,7 +216,7 @@ void ParserImpl::handleObject()
 	while (tok != JSON_OBJECT_END && checkError())
 	{
 		json_next(_pJSON);
-		if (_pHandler) _pHandler->key(std::string(json_get_string(_pJSON, NULL)));
+		if (_pHandler) _pHandler->key(std::string(json_get_string(_pJSON, nullptr)));
 		handle();
 		tok = json_peek(_pJSON);
 	}
@@ -252,7 +248,7 @@ void ParserImpl::handle()
 	case JSON_NUMBER:
 		if (_pHandler)
 		{
-			std::string str(json_get_string(_pJSON, NULL));
+			std::string str(json_get_string(_pJSON, nullptr));
 			if (str.find(_decimalPoint) != str.npos || str.find('e') != str.npos || str.find('E') != str.npos)
 			{
 				_pHandler->value(NumberParser::parseFloat(str));
diff --git a/JSON/src/PrintHandler.cpp b/JSON/src/PrintHandler.cpp
index 2bce27008f..b17727677a 100644
--- a/JSON/src/PrintHandler.cpp
+++ b/JSON/src/PrintHandler.cpp
@@ -41,9 +41,7 @@ PrintHandler::PrintHandler(std::ostream& out, unsigned indent, int options):
 }
 
 
-PrintHandler::~PrintHandler()
-{
-}
+PrintHandler::~PrintHandler() = default;
 
 
 void PrintHandler::reset()
diff --git a/JSON/src/Query.cpp b/JSON/src/Query.cpp
index 27e5ad8756..731681aaf1 100644
--- a/JSON/src/Query.cpp
+++ b/JSON/src/Query.cpp
@@ -37,9 +37,7 @@ Query::Query(const Var& source): _source(source)
 }
 
 
-Query::~Query()
-{
-}
+Query::~Query() = default;
 
 
 Object::Ptr Query::findObject(const std::string& path) const
@@ -51,7 +49,7 @@ Object::Ptr Query::findObject(const std::string& path) const
 	else if (result.type() == typeid(Object))
 		return new Object(result.extract<Object>());
 
-	return 0;
+	return nullptr;
 }
 
 
@@ -79,7 +77,7 @@ Array::Ptr Query::findArray(const std::string& path) const
 	else if (result.type() == typeid(Array))
 		return new Array(result.extract<Array>());
 
-	return 0;
+	return nullptr;
 }
 
 
@@ -150,7 +148,7 @@ Var Query::find(const std::string& path) const
 
 			if (!result.isEmpty() && !indexes.empty())
 			{
-				for (auto i: indexes)
+				for (const auto& i: indexes)
 				{
 					if (result.type() == typeid(Array::Ptr))
 					{
diff --git a/JSON/src/Stringifier.cpp b/JSON/src/Stringifier.cpp
index 78ced39215..e1f37de2f5 100644
--- a/JSON/src/Stringifier.cpp
+++ b/JSON/src/Stringifier.cpp
@@ -15,7 +15,6 @@
 #include "Poco/JSON/Stringifier.h"
 #include "Poco/JSON/Array.h"
 #include "Poco/JSON/Object.h"
-#include <iomanip>
 
 
 using Poco::Dynamic::Var;
@@ -34,28 +33,28 @@ void Stringifier::stringify(const Var& any, std::ostream& out, unsigned int inde
 
 	if (any.type() == typeid(Object))
 	{
-		Object& o = const_cast<Object&>(any.extract<Object>());
+		auto& o = const_cast<Object&>(any.extract<Object>());
 		o.setEscapeUnicode(escapeUnicode);
 		o.setLowercaseHex(lowercaseHex);
 		o.stringify(out, indent == 0 ? 0 : indent, step);
 	}
 	else if (any.type() == typeid(Array))
 	{
-		Array& a = const_cast<Array&>(any.extract<Array>());
+		auto& a = const_cast<Array&>(any.extract<Array>());
 		a.setEscapeUnicode(escapeUnicode);
 		a.setLowercaseHex(lowercaseHex);
 		a.stringify(out, indent == 0 ? 0 : indent, step);
 	}
 	else if (any.type() == typeid(Object::Ptr))
 	{
-		Object::Ptr& o = const_cast<Object::Ptr&>(any.extract<Object::Ptr>());
+		auto& o = const_cast<Object::Ptr&>(any.extract<Object::Ptr>());
 		o->setEscapeUnicode(escapeUnicode);
 		o->setLowercaseHex(lowercaseHex);
 		o->stringify(out, indent == 0 ? 0 : indent, step);
 	}
 	else if (any.type() == typeid(Array::Ptr))
 	{
-		Array::Ptr& a = const_cast<Array::Ptr&>(any.extract<Array::Ptr>());
+		auto& a = const_cast<Array::Ptr&>(any.extract<Array::Ptr>());
 		a->setEscapeUnicode(escapeUnicode);
 		a->setLowercaseHex(lowercaseHex);
 		a->stringify(out, indent == 0 ? 0 : indent, step);
@@ -66,7 +65,7 @@ void Stringifier::stringify(const Var& any, std::ostream& out, unsigned int inde
 	}
 	else if (any.isNumeric() || any.isBoolean())
 	{
-		std::string value = any.convert<std::string>();
+		auto value = any.convert<std::string>();
 		if ((Poco::icompare(value, "nan") == 0) ||
 			(Poco::icompare(value, "inf") == 0)) value = "null";
 		if (any.type() == typeid(char)) formatString(value, out, options);
@@ -74,7 +73,7 @@ void Stringifier::stringify(const Var& any, std::ostream& out, unsigned int inde
 	}
 	else if (any.isString() || any.isDateTime() || any.isDate() || any.isTime())
 	{
-		std::string value = any.convert<std::string>();
+		auto value = any.convert<std::string>();
 		formatString(value, out, options);
 	}
 	else
diff --git a/JSON/src/Template.cpp b/JSON/src/Template.cpp
index c452d6ee03..c9878a537d 100644
--- a/JSON/src/Template.cpp
+++ b/JSON/src/Template.cpp
@@ -32,17 +32,13 @@ POCO_IMPLEMENT_EXCEPTION(JSONTemplateException, Exception, "Template Exception")
 class Part
 {
 public:
-	Part()
-	{
-	}
+	Part() = default;
 
-	virtual ~Part()
-	{
-	}
+	virtual ~Part() = default;
 
 	virtual void render(const Var& data, std::ostream& out) const = 0;
 
-	typedef std::vector<SharedPtr<Part>> VectorParts;
+	using VectorParts = std::vector<SharedPtr<Part>>;
 };
 
 
@@ -57,11 +53,9 @@ class StringPart: public Part
 	{
 	}
 
-	virtual ~StringPart()
-	{
-	}
+	~StringPart() override = default;
 
-	void render(const Var& data, std::ostream& out) const
+	void render(const Var& data, std::ostream& out) const override
 	{
 		out << _content;
 	}
@@ -84,20 +78,16 @@ class StringPart: public Part
 class MultiPart: public Part
 {
 public:
-	MultiPart()
-	{
-	}
+	MultiPart() = default;
 
-	virtual ~MultiPart()
-	{
-	}
+	~MultiPart() override = default;
 
 	virtual void addPart(Part* part)
 	{
-		_parts.push_back(part);
+		_parts.emplace_back(part);
 	}
 
-	void render(const Var& data, std::ostream& out) const
+	void render(const Var& data, std::ostream& out) const override
 	{
 		for (const auto& p: _parts)
 		{
@@ -117,11 +107,9 @@ class EchoPart: public Part
 	{
 	}
 
-	virtual ~EchoPart()
-	{
-	}
+	~EchoPart() override = default;
 
-	void render(const Var& data, std::ostream& out) const
+	void render(const Var& data, std::ostream& out) const override
 	{
 		Query query(data);
 		Var value = query.find(_query);
@@ -144,9 +132,7 @@ class LogicQuery
 	{
 	}
 
-	virtual ~LogicQuery()
-	{
-	}
+	virtual ~LogicQuery() = default;
 
 	virtual bool apply(const Var& data) const
 	{
@@ -161,7 +147,7 @@ class LogicQuery
 				// An empty string must result in false, otherwise true
 				// Which is not the case when we convert to bool with Var
 			{
-				std::string s = value.convert<std::string>();
+				auto s = value.convert<std::string>();
 				logic = !s.empty();
 			}
 			else
@@ -188,11 +174,9 @@ class LogicExistQuery: public LogicQuery
 	{
 	}
 
-	virtual ~LogicExistQuery()
-	{
-	}
+	~LogicExistQuery() override = default;
 
-	virtual bool apply(const Var& data) const
+	bool apply(const Var& data) const override
 	{
 		Query query(data);
 		Var value = query.find(_queryString);
@@ -209,11 +193,9 @@ class LogicElseQuery: public LogicQuery
 	{
 	}
 
-	virtual ~LogicElseQuery()
-	{
-	}
+	~LogicElseQuery() override = default;
 
-	virtual bool apply(const Var& data) const
+	bool apply(const Var& data) const override
 	{
 		return true;
 	}
@@ -227,23 +209,21 @@ class LogicPart: public MultiPart
 	{
 	}
 
-	virtual ~LogicPart()
-	{
-	}
+	~LogicPart() override = default;
 
 	void addPart(LogicQuery* query, Part* part)
 	{
 		MultiPart::addPart(part);
-		_queries.push_back(query);
+		_queries.emplace_back(query);
 	}
 
-	void addPart(Part* part)
+	void addPart(Part* part) override
 	{
 		MultiPart::addPart(part);
 		_queries.push_back(new LogicElseQuery());
 	}
 
-	void render(const Var& data, std::ostream& out) const
+	void render(const Var& data, std::ostream& out) const override
 	{
 		int count = 0;
 		for (auto it = _queries.begin(); it != _queries.end(); ++it, ++count)
@@ -268,11 +248,9 @@ class LoopPart: public MultiPart
 	{
 	}
 
-	virtual ~LoopPart()
-	{
-	}
+	~LoopPart() override = default;
 
-	void render(const Var& data, std::ostream& out) const
+	void render(const Var& data, std::ostream& out) const override
 	{
 		Query query(data);
 
@@ -322,14 +300,12 @@ class IncludePart: public Part
 		}
 	}
 
-	virtual ~IncludePart()
-	{
-	}
+	~IncludePart() override = default;
 
-	void render(const Var& data, std::ostream& out) const
+	void render(const Var& data, std::ostream& out) const override
 	{
 		TemplateCache* cache = TemplateCache::instance();
-		if (cache == 0)
+		if (cache == nullptr)
 		{
 			Template tpl(_path);
 			tpl.parse();
@@ -348,16 +324,16 @@ class IncludePart: public Part
 
 
 Template::Template(const Path& templatePath):
-	_parts(0),
-	_currentPart(0),
+	_parts(nullptr),
+	_currentPart(nullptr),
 	_templatePath(templatePath)
 {
 }
 
 
 Template::Template():
-	_parts(0),
-	_currentPart(0)
+	_parts(nullptr),
+	_currentPart(nullptr)
 {
 }
 
@@ -430,24 +406,24 @@ void Template::parse(std::istream& in)
 			}
 
 			_partStack.push(_currentPart);
-			LoopPart* part = new LoopPart(loopVariable, query);
+			auto part = new LoopPart(loopVariable, query);
 			_partStack.push(part);
 			_currentPart->addPart(part);
 			_currentPart = part;
 		}
 		else if (command.compare("else") == 0)
 		{
-			if (_partStack.size() == 0)
+			if (_partStack.empty())
 			{
 				throw JSONTemplateException("Unexpected <? else ?> found");
 			}
 			_currentPart = _partStack.top();
-			LogicPart* lp = dynamic_cast<LogicPart*>(_currentPart);
-			if (lp == 0)
+			auto lp = dynamic_cast<LogicPart*>(_currentPart);
+			if (lp == nullptr)
 			{
 				throw JSONTemplateException("Missing <? if ?> or <? ifexist ?> for <? else ?>");
 			}
-			MultiPart* part = new MultiPart();
+			auto part = new MultiPart();
 			lp->addPart(part);
 			_currentPart = part;
 		}
@@ -459,18 +435,18 @@ void Template::parse(std::istream& in)
 				throw JSONTemplateException("Missing query in <? " + command + " ?>");
 			}
 
-			if (_partStack.size() == 0)
+			if (_partStack.empty())
 			{
 				throw JSONTemplateException("Unexpected <? elsif / elif ?> found");
 			}
 
 			_currentPart = _partStack.top();
-			LogicPart* lp = dynamic_cast<LogicPart*>(_currentPart);
-			if (lp == 0)
+			auto lp = dynamic_cast<LogicPart*>(_currentPart);
+			if (lp == nullptr)
 			{
 				throw JSONTemplateException("Missing <? if ?> or <? ifexist ?> for <? elsif / elif ?>");
 			}
-			MultiPart* part = new MultiPart();
+			auto part = new MultiPart();
 			lp->addPart(new LogicQuery(query), part);
 			_currentPart = part;
 		}
@@ -481,8 +457,8 @@ void Template::parse(std::istream& in)
 				throw JSONTemplateException("Unexpected <? endfor ?> found");
 			}
 			MultiPart* loopPart = _partStack.top();
-			LoopPart* lp = dynamic_cast<LoopPart*>(loopPart);
-			if (lp == 0)
+			auto lp = dynamic_cast<LoopPart*>(loopPart);
+			if (lp == nullptr)
 			{
 				throw JSONTemplateException("Missing <? for ?> command");
 			}
@@ -498,8 +474,8 @@ void Template::parse(std::istream& in)
 			}
 
 			_currentPart = _partStack.top();
-			LogicPart* lp = dynamic_cast<LogicPart*>(_currentPart);
-			if (lp == 0)
+			auto lp = dynamic_cast<LogicPart*>(_currentPart);
+			if (lp == nullptr)
 			{
 				throw JSONTemplateException("Missing <? if ?> or <? ifexist ?> for <? endif ?>");
 			}
@@ -516,7 +492,7 @@ void Template::parse(std::istream& in)
 				throw JSONTemplateException("Missing query in <? " + command + " ?>");
 			}
 			_partStack.push(_currentPart);
-			LogicPart* lp = new LogicPart();
+			auto lp = new LogicPart();
 			_partStack.push(lp);
 			_currentPart->addPart(lp);
 			_currentPart = new MultiPart();
@@ -590,7 +566,7 @@ std::string Template::readText(std::istream& in)
 				break;
 			}
 		}
-		text += c;
+		text += static_cast<char>(c);
 
 		c = in.get();
 	}
@@ -612,7 +588,7 @@ std::string Template::readTemplateCommand(std::istream& in)
 
 		if (c == '?' && in.peek() == '>')
 		{
-			in.putback(c);
+			in.putback(static_cast<char>(c));
 			break;
 		}
 
@@ -622,7 +598,7 @@ std::string Template::readTemplateCommand(std::istream& in)
 			break;
 		}
 
-		command += c;
+		command += static_cast<char>(c);
 
 		c = in.get();
 	}
@@ -638,7 +614,7 @@ std::string Template::readWord(std::istream& in)
 	while ((c = in.peek()) != -1 && !Ascii::isSpace(c))
 	{
 		in.get();
-		word += c;
+		word += static_cast<char>(c);
 	}
 	return word;
 }
@@ -652,7 +628,7 @@ std::string Template::readQuery(std::istream& in)
 	{
 		if (c == '?' && in.peek() == '>')
 		{
-			in.putback(c);
+			in.putback(static_cast<char>(c));
 			break;
 		}
 
@@ -660,7 +636,7 @@ std::string Template::readQuery(std::istream& in)
 		{
 			break;
 		}
-		word += c;
+		word += static_cast<char>(c);
 	}
 	return word;
 }
@@ -685,7 +661,7 @@ std::string Template::readString(std::istream& in)
 	{
 		while ((c = in.get()) != -1 && c != '"')
 		{
-			str += c;
+			str += static_cast<char>(c);
 		}
 	}
 	return str;
diff --git a/JSON/src/TemplateCache.cpp b/JSON/src/TemplateCache.cpp
index bb5c7e2702..5e0ad03abc 100644
--- a/JSON/src/TemplateCache.cpp
+++ b/JSON/src/TemplateCache.cpp
@@ -20,10 +20,10 @@ namespace Poco {
 namespace JSON {
 
 
-TemplateCache* TemplateCache::_pInstance = 0;
+TemplateCache* TemplateCache::_pInstance = nullptr;
 
 
-TemplateCache::TemplateCache(): _pLogger(0)
+TemplateCache::TemplateCache(): _pLogger(nullptr)
 {
 	setup();
 }
@@ -31,13 +31,13 @@ TemplateCache::TemplateCache(): _pLogger(0)
 
 TemplateCache::~TemplateCache()
 {
-	_pInstance = 0;
+	_pInstance = nullptr;
 }
 
 
 void TemplateCache::setup()
 {
-	poco_assert (_pInstance == 0);
+	poco_assert (_pInstance == nullptr);
 	_pInstance = this;
 }
 
@@ -61,7 +61,7 @@ Template::Ptr TemplateCache::getTemplate(const Path& path)
 
 	Template::Ptr tpl;
 
-	std::map<std::string, Template::Ptr>::iterator it = _cache.find(templatePathname);
+	auto it = _cache.find(templatePathname);
 	if (it == _cache.end())
 	{
 		if (templateFile.exists())