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PONull Pointer Exception: null error
 

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    <p>I have this Hash Set code and when I try to run my compile method on it I get the Null Pointer Exception: null error on it. Here is the code:</p> <pre><code>private void initKeywords() { keywords = new HashSet&lt;String&gt;(); keywords.add("final"); keywords.add("int"); keywords.add("while"); keywords.add("if"); keywords.add("else"); keywords.add("print"); } private boolean isIdent(String t) { if (keywords.contains(t)) { ***//This is the line I get the Error*** return false; } else if (t != null &amp;&amp; t.length() &gt; 0 &amp;&amp; Character.isLetter(t.charAt(0))) { return true; } else { return false; } } </code></pre> <p>The other lines that goes along with this error is: </p> <pre><code>public void compileProgram() { System.out.println("compiling " + filename); while (theToken != null) { if (equals(theToken, "int") || equals(theToken, "final")) { compileDeclaration(true); } else { compileFunction(); //This line is giving an error with the above error } } cs.emit(Machine.HALT); isCompiled = true; } private void compileFunction() { String fname = theToken; int entryPoint = cs.getPos(); if (equals(fname, "main")) { cs.setEntry(entryPoint); } if (isIdent(theToken)) theToken = t.token(); ***//This line is giving an error*** else t.error("expecting identifier, got " + theToken); symTable.allocProc(fname,entryPoint); accept("("); compileParamList(); accept(")"); compileCompound(true); if (equals(fname, "main")) cs.emit(Machine.HALT); else cs.emit(Machine.RET); } </code></pre>
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    1. USAlpdog14
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    1. COHey, remember to accept your answers.
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