Mercurial Hosting > luan

comparison src/goodjava/io/FixedLengthInputStream.java @ 1494:91c167099462

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
more io
author Franklin Schmidt <fschmidt@gmail.com>
date Sun, 03 May 2020 11:51:31 -0600
parents 9a2a2181a58f
children
comparison
equal deleted inserted replaced
1493:471ef3e6a84e 1494:91c167099462
1 package goodjava.io; 1 package goodjava.io;
2 2
3 import java.io.InputStream; 3 import java.io.InputStream;
4 import java.io.FilterInputStream;
5 import java.io.IOException; 4 import java.io.IOException;
6 import java.io.EOFException; 5 import java.io.EOFException;
7 6
8 7
9 public class FixedLengthInputStream extends FilterInputStream { 8 public class FixedLengthInputStream extends NoMarkInputStream {
10 protected long left; 9 protected long left;
11 10
12 public FixedLengthInputStream(InputStream in, long len) { 11 public FixedLengthInputStream(InputStream in, long len) {
13 super(in); 12 super(in);
14 if( len < 0 ) 13 if( len < 0 )
15 throw new IllegalArgumentException("len can't be negative"); 14 throw new IllegalArgumentException("len can't be negative");
16 this.left = len; 15 this.left = len;
17 } 16 }
18 17
19 public synchronized int read() throws IOException { 18 public int read() throws IOException {
20 if( left == 0 ) 19 if( left == 0 )
21 return -1; 20 return -1;
22 int n = super.read(); 21 int n = in.read();
23 if( n == -1 ) 22 if( n == -1 )
24 throw new EOFException(); 23 throw new EOFException();
25 left--; 24 left--;
26 return n; 25 return n;
27 } 26 }
28 27
29 public synchronized int read(byte[] b, int off, int len) throws IOException { 28 public int read(byte[] b, int off, int len) throws IOException {
30 if( len == 0 ) 29 if( len == 0 )
31 return 0; 30 return 0;
32 if( left == 0 ) 31 if( left == 0 )
33 return -1; 32 return -1;
34 if( len > left ) 33 if( len > left )
35 len = (int)left; 34 len = (int)left;
36 int n = super.read(b,off,len); 35 int n = in.read(b,off,len);
37 if( n == -1 ) 36 if( n == -1 )
38 throw new EOFException(); 37 throw new EOFException();
39 left -= n; 38 left -= n;
40 return n; 39 return n;
41 } 40 }
42 41
43 public synchronized long skip(long n) throws IOException { 42 public long skip(long n) throws IOException {
44 if( n > left ) 43 if( n > left )
45 n = left; 44 n = left;
46 n = in.skip(n); 45 n = in.skip(n);
47 left -= n; 46 left -= n;
48 return n; 47 return n;
49 } 48 }
50 49
51 public synchronized int available() throws IOException { 50 public int available() throws IOException {
52 int n = in.available(); 51 int n = in.available();
53 if( n > left ) 52 if( n > left )
54 n = (int)left; 53 n = (int)left;
55 return n; 54 return n;
56 } 55 }
57 56
58 public void mark(int readlimit) {}
59
60 public void reset() throws IOException {
61 throw new IOException("not supported");
62 }
63
64 public boolean markSupported() {
65 return false;
66 }
67
68 } 57 }