AudioHelper.java

package saic.media.audio.clint;

import java.io.File;
import java.io.IOException;

import android.media.MediaRecorder;
import android.os.Environment;

public class AudioHelper {
    final MediaRecorder recorder = new MediaRecorder();
      final String path;

      /**
       * Creates a new audio recording at the given path (relative to root of SD card).
       */
      public AudioHelper(String path) {
        this.path = sanitizePath(path);
      }

      private String sanitizePath(String path) {
        if (!path.startsWith("/")) {
          path = "/" + path;
        }
        if (!path.contains(".")) {
          path += ".3gp";
        }
        return Environment.getExternalStorageDirectory().getAbsolutePath() + path;
      }

      /**
       * Starts a new recording.
       */
      public void start() throws IOException {
        String state = android.os.Environment.getExternalStorageState();
        if(!state.equals(android.os.Environment.MEDIA_MOUNTED))  {
            throw new IOException("SD Card is not mounted.  It is " + state + ".");
        }

        // make sure the directory we plan to store the recording in exists
        File directory = new File(path).getParentFile();
        if (!directory.exists() && !directory.mkdirs()) {
          throw new IOException("Path to file could not be created.");
        }

        recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
        recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
        recorder.setOutputFile(path);
        recorder.prepare();
        recorder.start();
      }

      /**
       * Stops a recording that has been previously started.
       */
      public void stop() throws IOException {
        recorder.stop();
        //recorder.release();
      }
}