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1
21
22 package org.armedbear.lisp;
23
24 public final class BroadcastStream extends Stream
25 {
26 private final Stream[] streams;
27
28 private BroadcastStream(Stream[] streams) throws ConditionThrowable
29 {
30 this.streams = streams;
31 isOutputStream = true;
32 if (streams.length == 0) {
33 elementType = T;
34 isBinaryStream = true;
35 isCharacterStream = true;
36 } else {
37 elementType = streams[streams.length-1].getElementType();
38 if (elementType == Symbol.CHARACTER || elementType == Symbol.BASE_CHAR)
39 isCharacterStream = true;
40 else
41 isBinaryStream = true;
42 }
43 }
44
45 public Stream[] getStreams()
46 {
47 return streams;
48 }
49
50 public LispObject typeOf()
51 {
52 return Symbol.BROADCAST_STREAM;
53 }
54
55 public LispClass classOf()
56 {
57 return BuiltInClass.BROADCAST_STREAM;
58 }
59
60 public LispObject typep(LispObject typeSpecifier) throws ConditionThrowable
61 {
62 if (typeSpecifier == Symbol.BROADCAST_STREAM)
63 return T;
64 if (typeSpecifier == BuiltInClass.BROADCAST_STREAM)
65 return T;
66 return super.typep(typeSpecifier);
67 }
68
69 public LispObject listen() throws ConditionThrowable
70 {
71 notSupported();
72 return NIL;
74 }
75
76 public LispObject fileLength() throws ConditionThrowable
77 {
78 if (streams.length > 0)
79 return streams[streams.length - 1].fileLength();
80 else
81 return Fixnum.ZERO;
82 }
83
84 public LispObject fileStringLength(LispObject arg) throws ConditionThrowable
85 {
86 if (streams.length > 0)
87 return streams[streams.length - 1].fileStringLength(arg);
88 else
89 return Fixnum.ONE;
90 }
91
92 protected int _readChar() throws ConditionThrowable
94 {
95 notSupported();
96 return -1;
98 }
99
100 protected void _unreadChar(int n) throws ConditionThrowable
101 {
102 notSupported();
103 }
104
105 protected boolean _charReady() throws ConditionThrowable
106 {
107 notSupported();
108 return false;
110 }
111
112 public void _writeChar(char c) throws ConditionThrowable
113 {
114 for (int i = 0; i < streams.length; i++)
115 streams[i]._writeChar(c);
116 }
117
118 public void _writeChars(char[] chars, int start, int end)
119 throws ConditionThrowable
120 {
121 for (int i = 0; i < streams.length; i++)
122 streams[i]._writeChars(chars, start, end);
123 }
124
125 public void _writeString(String  s) throws ConditionThrowable
126 {
127 for (int i = 0; i < streams.length; i++)
128 streams[i]._writeString(s);
129 }
130
131 public void _writeLine(String s) throws ConditionThrowable
132 {
133 for (int i = 0; i < streams.length; i++)
134 streams[i]._writeLine(s);
135 }
136
137 public int _readByte() throws ConditionThrowable
139 {
140 notSupported();
141 return -1;
143 }
144
145 public void _writeByte(int n) throws ConditionThrowable
147 {
148 for (int i = 0; i < streams.length; i++)
149 streams[i]._writeByte(n);
150 }
151
152 public void _finishOutput() throws ConditionThrowable
153 {
154 for (int i = 0; i < streams.length; i++)
155 streams[i]._finishOutput();
156 }
157
158 public void _clearInput() throws ConditionThrowable
159 {
160 notSupported();
161 }
162
163 protected long _getFilePosition() throws ConditionThrowable
164 {
165 if (streams.length == 0)
166 return 0;
167 else
168 return streams[streams.length-1]._getFilePosition();
169 }
170
171 protected boolean _setFilePosition(LispObject arg) throws ConditionThrowable
172 {
173 return false;
174 }
175
176 public void _close() throws ConditionThrowable
177 {
178 setOpen(false);
179 }
180
181 private void notSupported() throws ConditionThrowable
182 {
183 signal(new TypeError("Operation is not supported for streams of type BROADCAST-STREAM."));
184 }
185
186 private static final Primitive MAKE_BROADCAST_STREAM =
188 new Primitive("make-broadcast-stream", "&rest streams")
189 {
190 public LispObject execute(LispObject[] args) throws ConditionThrowable
191 {
192 Stream[] streams = new Stream[args.length];
193 for (int i = 0; i < args.length; i++) {
194 if (args[i] instanceof Stream) {
195 if (((Stream)args[i]).isOutputStream()) {
196 streams[i] = (Stream) args[i];
197 continue;
198 }
199 }
200 signal(new TypeError(String.valueOf(args[i]) +
201 " is not an output stream."));
202 }
203 return new BroadcastStream(streams);
205 }
206 };
207
208 private static final Primitive1 BROADCAST_STREAM_STREAMS =
210 new Primitive1("broadcast-stream-streams", "broadcast-stream")
211 {
212 public LispObject execute(LispObject arg) throws ConditionThrowable
213 {
214 try {
215 BroadcastStream stream = (BroadcastStream) arg;
216 Stream[] streams = stream.streams;
217 LispObject result = NIL;
218 for (int i = streams.length; i-- > 0;)
219 result = new Cons(streams[i], result);
220 return result;
221 }
222 catch (ClassCastException e) {
223 return signal(new TypeError(arg, Symbol.BROADCAST_STREAM));
224 }
225 }
226 };
227 }
228 |
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