File	Doc	Category	Size	Date	Package
DigestInputStream.java	API Doc	Android 1.5 API	5150	Wed May 06 22:41:06 BST 2009	java.security

DigestInputStream

• java.lang.Object
  • java.io.InputStream
    • java.io.FilterInputStream

Fields Summary
protected MessageDigest	digest The message digest for this stream.
private boolean	isOn

Constructors Summary
public DigestInputStream(InputStream stream, MessageDigest digest) Constructs a new instance of this {@code DigestInputStream}, using the given {@code stream} and the {@code digest}. param stream the input stream. param digest the message digest. since Android 1.0 super(stream); this.digest = digest;

Methods Summary
public java.security.MessageDigest	getMessageDigest() Returns the message digest for this stream. return the message digest for this stream. since Android 1.0 return digest;
public void	on(boolean on) Enables or disables the digest function (default is on). param on {@code true} if the digest should be computed, {@code false} otherwise. since Android 1.0 isOn = on;
public int	read() Reads the next byte and returns it as an {@code int}. Updates the digest for the byte if this function is {@link #on(boolean)}. This operation is blocking. return the byte which was read or -1 at end of stream. throws IOException if reading the source stream causes an {@code IOException}. since Android 1.0 // read the next byte int byteRead = in.read(); // update digest only if // - digest functionality is on // - eos has not been reached if (isOn && (byteRead != -1)) { digest.update((byte)byteRead); } // return byte read return byteRead;
public int	read(byte[] b, int off, int len) Reads {@code len} bytes into the specified {@code byte[]}, starting from the specified offset. Updates the digest if this function is {@link #on(boolean)}. This operation is blocking. param b the byte array in which to store the bytes param off the initial position in {@code b} to store the bytes read from this stream param len the maximum number of bytes to store in {@code b} return the number of bytes actually read or -1 if the end of the filtered stream has been reached while reading throws IOException if reading the source stream causes an {@code IOException} since Android 1.0 // read next up to len bytes int bytesRead = in.read(b, off, len); // update digest only if // - digest functionality is on // - eos has not been reached if (isOn && (bytesRead != -1)) { digest.update(b, off, bytesRead); } // return number of bytes read return bytesRead;
public void	setMessageDigest(java.security.MessageDigest digest) Sets the message digest which this stream will use. param digest the message digest which this stream will use. since Android 1.0 this.digest = digest;
public java.lang.String	toString() Returns a string containing a concise, human-readable description of this {@code DigestInputStream} including the digest. return a printable representation for this {@code DigestInputStream}. since Android 1.0 return super.toString() + ", " + digest.toString() + //$NON-NLS-1$ (isOn ? ", is on" : ", is off"); //$NON-NLS-1$ //$NON-NLS-2$