prod/net/jaekl/qd/util/FileIO.java

   1 package net.jaekl.qd.util;
   2
   3 import java.io.File;
   4 import java.io.FileInputStream;
   5 import java.io.FileNotFoundException;
   6 import java.io.FileOutputStream;
   7 import java.io.InputStream;
   8 import java.io.OutputStream;
   9
  10 // Dispatch File Input/Output operations from a singleton
  11 // This makes it possible to intercept file reads and writes
  12 // during unit testing, and replace them with mock operations.
  13
  14 public class FileIO {
  15         // Note:  need volatile to implement double-checked locking in getInst()
  16         static volatile FileIO m_inst = null;
  17
  18         FileIO() { ; }
  19
  20         public static FileIO getInst() {
  21                 FileIO result = m_inst;
  22                 if (null == result) {
  23                         synchronized(FileIO.class) {
  24                                 if (null == m_inst) {
  25                                         m_inst = new FileIO();
  26                                 }
  27                                 result = m_inst;
  28                         }
  29                 }
  30                 return result;
  31         }
  32
  33         public InputStream openInput(File file) throws FileNotFoundException
  34         {
  35                 return new FileInputStream(file);
  36         }
  37
  38         public OutputStream openOutput(File file) throws FileNotFoundException
  39         {
  40                 return new FileOutputStream(file);
  41         }
  42 }