[Demonstration 1]

[Buggy Method]
@Test
public void byDefaultCanSetFieldsValues() {
    assertEquals(viewModel.getCoordinate1X(), "");
    assertEquals(viewModel.getCoordinate1Y(), "");
    assertEquals(viewModel.getCoordinate1Z(), "");
    assertEquals(viewModel.getCoordinate2X(), "");
    assertEquals(viewModel.getCoordinate2Y(), "");
    assertEquals(viewModel.getCoordinate2Z(), "");
    assertEquals(viewModel.getCoordinate3X(), "");
    assertEquals(viewModel.getCoordinate3Y(), "");
    assertEquals(viewModel.getCoordinate3Z(), "");
    assertEquals(viewModel.getValueToCalculate(), ValuesToCalculate.PERIMETER);
    assertEquals(viewModel.getResult(), "0.0");
}

[Buggy Hunk]
assertEquals(viewModel.getValueToCalculate(), ValuesToCalculate.PERIMETER);

[Patch]
assertEquals(viewModel.getValueToCalculate(), ValuesToCalculate.MEDIANS);

[Demonstration 2]

[Buggy Method]
public boolean removeField(String nameOfFieldToDelete) {
    boolean wasSuccessful = false;
    if (getFieldIndexByName(nameOfFieldToDelete) == -1 || getFieldIndexByName(nameOfFieldToDelete) >= fieldContents.size()) {
        fieldContents.remove(getFieldIndexByName(nameOfFieldToDelete));
        fieldNames.remove(getFieldIndexByName(nameOfFieldToDelete));
        wasSuccessful = updateContactFile();
    } else {
        wasSuccessful = false;
    }
    return wasSuccessful;
}

[Buggy Hunk]
if(getFieldIndexByName(nameOfFieldToDelete) == -1 || getFieldIndexByName(nameOfFieldToDelete) >= fieldContents.size()){

[Patch]
if(getFieldIndexByName(nameOfFieldToDelete) != -1 || getFieldIndexByName(nameOfFieldToDelete) >= fieldContents.size()){

[Demonstration 3]

[Buggy Method]
public static <T extends CharSequence> T deleteAll(final boolean matchCase, final T container, final T sequence) {
    T charSequence = container;
    int index;
    while ((index = indexOf(matchCase, charSequence, sequence)) > -1) {
        if (container instanceof StringBuilder) {
            charSequence = (T) ((StringBuilder) container).delete(index, index + sequence.length());
        } else if (container instanceof StringBuffer) {
            charSequence = (T) ((StringBuffer) container).delete(index, index + sequence.length());
        } else {
            charSequence = (T) (container.subSequence(0, index).toString() + container.subSequence(index + sequence.length(), container.length()));
        }
    }
    return charSequence;
}

[Buggy Hunk]
charSequence = (T) (container.subSequence(0, index).toString() + container.subSequence(index + sequence.length(), container.length()));

[Patch]
charSequence = (T) (charSequence.subSequence(0, index).toString() + charSequence.subSequence(index + sequence.length(), charSequence.length()));