Duplication

 public String insertCodeBlock(String newBlock) {
        String text = textArea.getText();
        int start = 0;
        int count = 0;
        String buildNewTextArea = "";
        while (start >= 0) {
            int nextLineStart = text.indexOf(NEW_LINE, start + NEW_LINE.length());
            if (nextLineStart == -1) {
                nextLineStart = text.length();
            }
            String[] temp = diffBlocks.get(indexOfLine).split(",");
            int startLine = Integer.valueOf(temp[0]);
            int endLine = (Integer.valueOf(temp[1]) - 1) + startLine;
            if (count == startLine) {
                buildNewTextArea += newBlock;
            } else if (count < startLine || count > (startLine + (endLine - startLine))) {
                buildNewTextArea += text.substring(start, nextLineStart);
            }
            count++;
            start = text.indexOf(NEW_LINE, nextLineStart);
        }
        return buildNewTextArea;
    }

    private int getLineIndex(int line) {
        String text = textArea.getText();
        int start = 0;
        int count = 0;
        String buildNewTextArea = "";
        int index = 0;
        while (start >= 0) {
            int nextLineStart = text.indexOf(NEW_LINE, start + NEW_LINE.length());
            if (nextLineStart == -1) {
                nextLineStart = text.length();
            }
            if (count == line) {
                return index;
            }
            buildNewTextArea = text.substring(start, nextLineStart);
            index += buildNewTextArea.length();
            count++;
            start = text.indexOf(NEW_LINE, nextLineStart);
        }
        return text.length();
    }


    public String getLineContent(int startLine, int endLine) {
        String text = textArea.getText();
        int start = 0;
        int count = 0;
        String buildNewTextArea = "";
        while (start >= 0) {
            int nextLineStart = text.indexOf(NEW_LINE, start + NEW_LINE.length());
            if (nextLineStart == -1) {
                nextLineStart = text.length();
            }
            if (count >= startLine && count <= endLine) {
                buildNewTextArea += text.substring(start, nextLineStart);
            }
            count++;
            start = text.indexOf(NEW_LINE, nextLineStart);
        }
        return buildNewTextArea;
    }