HemingwayApp

An amazing online tool to proof read your essay!

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Online Tools | Dev buddies

Some of the very useful day to day online tools that can help a jdeveloper a lot
RegEx matcher
http://www.gskinner.com/RegExr/

JSON formatter
http://jsonlint.com/

XML tools
XML formatter
http://www.xmltoolbox.com/
XML to XSD converter
http://www.freeformatter.com/xsd-generator.html#ad-output
Use 'xjc' tool to convert the XSD to Java pojo classes which can be used to marshall and unmarshall using JAXB

Unicode tools
http://www.online-toolz.com/tools/text-unicode-entities-convertor.php

Diff tool
http://text-compare.com/

Eclipse Memory Analyzer

An amazing open source free tool to do memory profiling

http://www.eclipse.org/mat/

Apache TIKA: Content Analysis Toolkit

Apache TIKA - is a very powerful tool for analyzing documents of almost any format!
http://tika.apache.org/