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    <p>You can do it by <a href="http://en.wikipedia.org/wiki/Lexical_analysis" rel="nofollow">Lexical Analysis</a>. There are many lexical generator for java like: JavaCC , JLex etc.</p> <p>Or you can use something like pre/post -fix calculator or stack calculator for parenthesis balancing and to maintain the hierarchy, originally it is done by <a href="http://en.wikipedia.org/wiki/Tree_traversal" rel="nofollow">traversing through a "tree"</a> and in that calculator in place of "1"-"9" numbers (which comes as string) you have to match "true" or "false" and in place of "+", "-" binary operator you have to match and operate "and" and "or"! </p> <p>I have made a Boolean Algebra Parser as I have committed in my previous comment, I think it works, you are also welcome to fork and contribute: <a href="https://github.com/sadaf2605/Java-Boolean-Algebra-Parser" rel="nofollow">https://github.com/sadaf2605/Java-Boolean-Algebra-Parser</a></p> <p>code:</p> <pre><code>public class BooleanAlgebra { static final String CONST_and="And"; static final String CONST_or="Or"; static final String CONST_true="True"; static final String CONST_false="False"; public static void main(String[] args) { System.out.println(booleanAlgebra("False")==false); System.out.println(booleanAlgebra("True")==true); System.out.println(booleanAlgebra("False And False")==false); System.out.println(booleanAlgebra("True And False")==false); System.out.println(booleanAlgebra("True And True")==true); System.out.println(booleanAlgebra("False And True")==false); System.out.println(booleanAlgebra("(False And True)")==false); System.out.println(booleanAlgebra("True Or (False And True)")==true); System.out.println(booleanAlgebra("(True And False) And (False And True) Or True")==true); System.out.println(booleanAlgebra("( (True And False) Or True )")==true); System.out.println(booleanAlgebra("( False Or (True And (False Or True)) Or True )")==true); } static boolean booleanAlgebra(String str){ return TrueFalse(str, false, "Or"); } static boolean TrueFalse(String s,boolean b, String op){ boolean btemp=false; s=s.replaceAll(" ", ""); while(!s.isEmpty()){ if(s.startsWith(CONST_true)){ btemp=true; s=s.substring(4); }else if(s.startsWith(CONST_false)){ btemp=false; s=s.substring(5); }else if(s.startsWith(CONST_and)){ op=CONST_and; s=s.substring(3); }else if(s.startsWith(CONST_or)){ op=CONST_or; s=s.substring(2); }else if(s.startsWith("(")){ int end=s.indexOf(")"); if(end&gt;0){ b=TrueFalse(s.substring(1, end&gt;-1?end:1),b,op); s=s.substring(end); } }else{ s=s.substring(1); } if (op.equals(CONST_and)){ b=b&amp;&amp;btemp; }else if(op.equals(CONST_or)){ b=b||btemp; } } return b; } } </code></pre>
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    1. POHow to represent boolean algebra strings?
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    1. COI'm curious! Concerning your question: yes the overall intention is finally to return `boolean` (in the backend) of the conducted expression.
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    2. COHey @membersound I have added my code at github :)
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    3. COUsing the index of the closing parenthesis doesn't handle nested parenthesis.
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