Where in my class code (Java) is causing the error messages? Please help rewrite the code!

import java.util.ArrayList;

/** * This is the Polynomial Implementation class that implements the Polynomial interface. */ public class PolynomialImpl implements Polynomial {

private final ArrayList terms;

/** * This is the constructor. */ public PolynomialImpl() { terms = new ArrayList(); }

/** * This method adds the resulting term to the Polynomial. * @param coeff the coefficient of the term. * @param power the power of the term (the exponent). */ @Override public void addTerm(int coeff, int power) { if (coeff != 0) { Term newTerm = new Term(coeff, power); addTerm(newTerm, 0); } }

/** * This method is the helper method for addTerm(int coeff, int power) method. * * @param newTerm new term to add * @param termNum term index in the terms list */ private void addTerm(Term newTerm, int termNum) { if (termNum >= terms.size()) { this.terms.add(termNum, newTerm); } else { if (this.terms.get(termNum).power > newTerm.power) { addTerm(newTerm, termNum + 1); } else if (this.terms.get(termNum).power == newTerm.power) { this.terms.get(termNum).coeff += newTerm.coeff; if (this.terms.get(termNum).coeff == 0) { this.terms.remove(termNum); } } else { this.terms.add(termNum, newTerm); } } }

/** * This method removes any and all terms in the Polynomial with the given power. * @param power the power of the term to remove */ @Override public void removeTerm(int power) { removeTerm(power, 0); }

/** * This method is a helper for removeTerm(int power) method. * @param power the power of the term to remove * @param termNum term index in the terms list */ private void removeTerm(int power, int termNum) { if (termNum power) { removeTerm(power, termNum + 1); } else if (this.terms.get(termNum).power == power) { this.terms.remove(termNum); } } }

/** *This method computes the degree of the Polynomial. * @return return of the degree value */ @Override public int getDegree() { if (!this.terms.isEmpty()) { return this.terms.get(0).power; } else { throw new IllegalArgumentException("A term with negative power should not work, but did. "); } }

/** * This method computes the coefficient of a term with the given power. * @param power the power of the term to find * @return coefficient */ @Override public int getCoefficient(int power) { return getCoefficient(power, 0); }

/** * This method is a helper method for getCoefficient(int power) method. * @param power the power of the term to find * @param termNum the term index in the terms list * @return the value of 0 */ private int getCoefficient(int power, int termNum) { if (termNum >= terms.size()) { return 0; } if (this.terms.get(termNum).power == power) { return this.terms.get(termNum).coeff; } else if (this.terms.get(termNum).power > power) { return getCoefficient(power, termNum + 1); } else { return 0; } }

/** * This method adds this Polynomial with the given Polynomial * and return the resulting Polynomial. * @param p the Polynomial to add to this Polynomial * @return the sum of adding two Polynomials */ @Override public Polynomial add(Polynomial p) { //Create Polynomial to hold the sum Polynomial sum = new PolynomialImpl();

//Add this Polynomial to sum add(sum, this, 0);

//Add Polynomial p to sum add(sum, p, 0);

//Return sum return sum; }

/** * This method is a helper method for the add(Polynomial p) method. * @param p1 the Polynomial to which Polynomial (p2) will be added * @param p2 the Polynomial to which Polynomial (p1) will be added * @param termNum the term index in the terms list */ private void add(Polynomial p1, Polynomial p2, int termNum) { if (termNum >= ((PolynomialImpl) p2).terms.size()) { return; } p1.addTerm(((PolynomialImpl) p2).terms.get(termNum).coeff, ((PolynomialImpl) p2).terms.get(termNum).power); add(p1, p2, termNum + 1); }

@Override public double evaluate(double x) { /*if (coeff != null) { for (int i = getCoefficient().length - 1; i >= 0; --i); value = getCofficient[i] + (x * value); }*/ return x; }

@Override public String toString() { if (terms.isEmpty()) { return "0"; } else { StringBuilder sb = new StringBuilder(); for (int i = 0; i

//INNER CLASS static class Term {

private int coeff; private final int power;

/** * This is the Parameterized constructor. * @param coeff the coefficient of the Term * @param power this is the power of the Term */ public Term(int coeff, int power) { this.coeff = coeff; this.power = power; }

@Override public String toString() { if (this.coeff == 0) { return "0"; } else if (power == 0) { if (this.coeff Failed: testinvalidPolynomialCreation By Term(GraderPolynomialVisible Test) Message: A term with negative power should not work, but did. Failed: testEvaluate(GraderPolynomialVisible Test) Message: For f(x)=15x^26 f(1.01) should be 19.428844724511094 but is 1.01 expected: but was: Failed: testinvalidPolynomialCreation By Term(GraderPolynomialVisible Test) Message: A term with negative power should not work, but did. Failed: testEvaluate(GraderPolynomialVisible Test) Message: For f(x)=15x^26 f(1.01) should be 19.428844724511094 but is 1.01 expected: but was: