Package umontreal.ssj.util.io

This subpackage provides tools for exporting data to text and binary files, as well as for importing data from files. More...

Classes
class	AbstractDataReader
	This abstract class implements shared functionality for data readers. More...
class	AbstractDataWriter
	This abstract class implements shared functionality for data writers. More...
class	BinaryDataReader
	Binary data reader. More...
class	BinaryDataWriter
	Binary data writer. More...
class	CachedDataWriter
	This abstract class implements shared functionality for data writers that store all fields in memory before outputing them with umontreal.ssj.util.io.DataWriter.close. More...
class	DataField
	This class represents a data field from a file read by an instance of a class implementing DataReader. More...
interface	DataReader
	Data reader interface. More...
interface	DataWriter
	Data writer interface. More...
class	TextDataWriter
	Text data writer. More...

Detailed Description

This subpackage provides tools for exporting data to text and binary files, as well as for importing data from files.

Each of the write() methods takes a field label as their first argument. This label can always be set to null, in which case an anonymous field will be written. The write() methods that take one-dimensional array argument can also take an additional integer argument, for convenience, to specify the number of elements to write in the array.

For a quick start, consult the following examples and the documentation for umontreal.ssj.util.io.DataWriter and umontreal.ssj.util.io.DataReader, as well as the constructors of implementing classes ( umontreal.ssj.util.io.TextDataWriter, umontreal.ssj.util.io.BinaryDataWriter and umontreal.ssj.util.io.BinaryDataReader ).

Example of how to write data to a file:

public static void writerExample() throws IOException {
   String filename = "test.dat";
   DataWriter out = new BinaryDataWriter(filename);
   out.write("zero", 0);
   out.write("zerotxt", "ZERO");
   out.write("n", new int[]{1,2,3,4,5});
   out.write("pi", Math.PI);
   out.write("str", new String[]{"text1", "text2"});
   out.write("real", new double[]{2.5, 3.7, 8.9});
   out.write("real2", new float[]{2.5f, 3.7f, 8.9f});
   out.write(null, 24);
   out.write(null, 39);
   out.write(null, 116);
   out.close();
}

Example of how to read data from a file — specific fields:

public static void readerExample1() throws IOException {
   String filename = "test.dat";
   DataReader in = new BinaryDataReader(filename);
 
   // read double field labeled "pi"
   System.out.println("[pi] (double) " + in.readField("pi").asDouble());
 
   // read integer-array field labeled "n"
   int[] n = in.readIntArray("n");
   System.out.print("[n] (int[]) ");
   for (int i = 0; i < n.length; i++)
      System.out.print(" " + n[i]);
   System.out.println();
 
   in.close();
}

Example of how to read data from a file — list all fields:

public static void readerExample2() throws IOException {
   String filename = "test.dat";
   DataReader in = new BinaryDataReader(filename);
 
   Map<String,DataField> fields = in.readAllFields();
   in.close();
 
   // sort keys
   Set<String> allKeys = new TreeSet<String>(fields.keySet());
 
   for (String key : allKeys) {
      System.out.print("[" + key + "]");
      DataField d = fields.get(key);
 
      if (d.isString())
         System.out.print(" (String) " + d.asString());
 
      if (d.isInt())
         System.out.print(" (int) " + d.asInt());
 
      if (d.isFloat())
         System.out.print(" (float) " + d.asFloat());
 
      if (d.isDouble())
         System.out.print(" (double) " + d.asDouble());
 
      if (d.asStringArray() != null) {
         System.out.print(" (String[]) ");
         String[] a = d.asStringArray();
         for (int i = 0; i < a.length; i++)
            System.out.print(" " + a[i]);
      }
 
      if (d.asIntArray() != null) {
         System.out.print(" (int[]) ");
         int[] a = d.asIntArray();
         for (int i = 0; i < a.length; i++)
            System.out.print(" " + a[i]);
      }
 
      if (d.asFloatArray() != null) {
         System.out.print(" (float[]) ");
         float[] a = d.asFloatArray();
         for (int i = 0; i < a.length; i++)
            System.out.print(" " + a[i]);
      }
 
      if (d.asDoubleArray() != null) {
         System.out.print(" (double[]) ");
         double[] a = d.asDoubleArray();
         for (int i = 0; i < a.length; i++)
            System.out.print(" " + a[i]);
      }
 
      System.out.println();
   }
}