title: Read and Write CSV File using Java
body: <p>I have a CSV log file and it contains many rows like this:</p>
  
  <pre><code>2016-06-21 12:00:00,000 : helloworld: header1=2;header2=6;header=0
  </code></pre>
  
  <p>I want to write them to a new CSV file.</p>
  
  <pre><code>public void readLogFile() throws Exception
  {
      String currentLine = "";
      String nextLine = "";
  
      BufferedReader reader = new BufferedReader(new FileReader(file(false)));
      while ((currentLine = reader.readLine()) != null)
      {
          if (currentLine.contains("2016") == true)
          {
              nextLine = reader.readLine();
              if (nextLine.contains("helloworld") == true)
              {                   
                  currentLine = currentLine.substring(0, 23);
                  nextLine = nextLine.substring(22, nextLine.length());
  
                  String nextBlock = replaceAll(nextLine);
                  System.out.println(currentLine + " : helloworld: " + nextBlock);
  
                  String[] data = nextBlock.split(";");
                  for (int i = 0, max = data.length; i &lt; max; i++)
                  {
                      String[] d = data[i].split("=");
                      map.put(d[0], d[1]);
                  }
              }
          }
      }
      reader.close();
  }
  </code></pre>
  
  <p>This is my method to write the content:</p>
  
  <pre><code>public void writeContentToCsv() throws Exception
  {
      FileWriter writer = new FileWriter(".../file_new.csv");
      for (Map.Entry&lt;String, String&gt; entry : map.entrySet())
      {
          writer.append(entry.getKey()).append(";").append(entry.getValue()).append(System.getProperty("line.separator"));
      }
      writer.close();
  }
  </code></pre>
  
  <p>This is the output I want to have:</p>
  
  <pre><code>header1; header2; header3
  2;6;0
  1;5;1
  5;8;8
  ...
  </code></pre>
  
  <p>Currently, the CSV file looks like this (only showing one dataset):</p>
  
  <pre><code>header1;4
  header2;0
  header3;0
  </code></pre>
  
  <p>Can anyone help me fix the code?</p>