src/main/java/org/apache/james/mime4j/BufferingInputStreamAdaptor.java

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  19
  20 package org.apache.james.mime4j;
  21
  22 import java.io.IOException;
  23 import java.io.InputStream;
  24
  25 /**
  26  * <code>InputStream</code> used by the MIME parser to detect whether the
  27  * underlying data stream was used (read from) and whether the end of the
  28  * stream was reached.
  29  *
  30  * @version $Id$
  31  */
  32 class BufferingInputStreamAdaptor extends BufferingInputStream {
  33
  34     private final InputStream is;
  35     private final BufferingInputStream bis;
  36     private boolean used = false;
  37     private boolean eof = false;
  38
  39     public BufferingInputStreamAdaptor(final InputStream is) {
  40         super();
  41         this.is = is;
  42         if (is instanceof BufferingInputStream) {
  43             this.bis = (BufferingInputStream) is;
  44         } else {
  45             this.bis = null;
  46         }
  47     }
  48
  49     public int read() throws IOException {
  50         int i = this.is.read();
  51         this.eof = i == -1;
  52         this.used = true;
  53         return i;
  54     }
  55
  56     public int read(byte[] b, int off, int len) throws IOException {
  57         int i = this.is.read(b, off, len);
  58         this.eof = i == -1;
  59         this.used = true;
  60         return i;
  61     }
  62
  63     public int readLine(final ByteArrayBuffer dst) throws IOException {
  64         int i;
  65         if (this.bis != null) {
  66              i = this.bis.readLine(dst);
  67         } else {
  68              i = doReadLine(dst);
  69         }
  70         this.eof = i == -1;
  71         this.used = true;
  72         return i;
  73     }
  74
  75     private int doReadLine(final ByteArrayBuffer dst) throws IOException {
  76         int total = 0;
  77         int ch;
  78         while ((ch = this.is.read()) != -1) {
  79             dst.append(ch);
  80             total++;
  81             if (ch == '\n') {
  82                 break;
  83             }
  84         }
  85         if (total == 0 && ch == -1) {
  86             return -1;
  87         } else {
  88             return total;
  89         }
  90     }
  91
  92     public boolean eof() {
  93         return this.eof;
  94     }
  95
  96     public boolean isUsed() {
  97         return this.used;
  98     }
  99
 100 }