1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.pdfbox.pdfwriter;
18
19 import java.io.IOException;
20 import java.io.OutputStream;
21
22 import java.util.Iterator;
23 import java.util.List;
24 import java.util.Map;
25
26 import org.apache.pdfbox.cos.COSArray;
27 import org.apache.pdfbox.cos.COSBase;
28 import org.apache.pdfbox.cos.COSBoolean;
29 import org.apache.pdfbox.cos.COSDictionary;
30 import org.apache.pdfbox.cos.COSFloat;
31 import org.apache.pdfbox.cos.COSInteger;
32 import org.apache.pdfbox.cos.COSName;
33 import org.apache.pdfbox.cos.COSString;
34
35 import org.apache.pdfbox.util.ImageParameters;
36 import org.apache.pdfbox.util.PDFOperator;
37
38 /**
39 * A class that will take a list of tokens and write out a stream with them.
40 *
41 * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
42 * @version $Revision: 1.8 $
43 */
44 public class ContentStreamWriter
45 {
46 private OutputStream output;
47 /**
48 * space character.
49 */
50 public static final byte[] SPACE = new byte[] { 32 };
51
52 /**
53 * standard line separator on this platform.
54 */
55 public static final byte[] EOL = System.getProperty("line.separator").getBytes();
56
57 /**
58 * This will create a new content stream writer.
59 *
60 * @param out The stream to write the data to.
61 */
62 public ContentStreamWriter( OutputStream out )
63 {
64 output = out;
65 }
66
67 /**
68 * This will write out the list of tokens to the stream.
69 *
70 * @param tokens The tokens to write to the stream.
71 * @param start The start index into the list of tokens.
72 * @param end The end index into the list of tokens.
73 * @throws IOException If there is an error writing to the stream.
74 */
75 public void writeTokens( List tokens, int start, int end ) throws IOException
76 {
77 for( int i=start; i<end; i++ )
78 {
79 Object o = tokens.get( i );
80 writeObject( o );
81 //write a space between each object.
82 output.write( 32 );
83 }
84 output.flush();
85 }
86
87 private void writeObject( Object o ) throws IOException
88 {
89 if( o instanceof COSString )
90 {
91 ((COSString)o).writePDF( output );
92 }
93 else if( o instanceof COSFloat )
94 {
95 ((COSFloat)o).writePDF( output );
96 }
97 else if( o instanceof COSInteger )
98 {
99 ((COSInteger)o).writePDF( output );
100 }
101 else if( o instanceof COSBoolean )
102 {
103 ((COSBoolean)o).writePDF( output );
104 }
105 else if( o instanceof COSName )
106 {
107 ((COSName)o).writePDF( output );
108 }
109 else if( o instanceof COSArray )
110 {
111 COSArray array = (COSArray)o;
112 output.write(COSWriter.ARRAY_OPEN);
113 for( int i=0; i<array.size(); i++ )
114 {
115 writeObject( array.get( i ) );
116 output.write( SPACE );
117 }
118
119 output.write( COSWriter.ARRAY_CLOSE );
120 }
121 else if( o instanceof COSDictionary )
122 {
123 COSDictionary obj = (COSDictionary)o;
124 output.write( COSWriter.DICT_OPEN );
125 for (Map.Entry<COSName, COSBase> entry : obj.entrySet())
126 {
127 if (entry.getValue() != null)
128 {
129 writeObject( entry.getKey() );
130 output.write( SPACE );
131 writeObject( entry.getValue() );
132 output.write( SPACE );
133 }
134 }
135 output.write( COSWriter.DICT_CLOSE );
136 output.write( SPACE );
137 }
138 else if( o instanceof PDFOperator )
139 {
140 PDFOperator op = (PDFOperator)o;
141 if( op.getOperation().equals( "BI" ) )
142 {
143 output.write( "BI".getBytes() );
144 ImageParameters params = op.getImageParameters();
145 COSDictionary dic = params.getDictionary();
146 for( COSName key : dic.keySet() )
147 {
148 Object value = dic.getDictionaryObject( key );
149 key.writePDF( output );
150 output.write( SPACE );
151 writeObject( value );
152 output.write( EOL );
153 }
154 output.write( "ID".getBytes() );
155 output.write( EOL );
156 output.write( op.getImageData() );
157 }
158 else
159 {
160 output.write( op.getOperation().getBytes() );
161 output.write( EOL );
162 }
163 }
164 else
165 {
166 throw new IOException( "Error:Unknown type in content stream:" + o );
167 }
168 }
169
170 /**
171 * This will write out the list of tokens to the stream.
172 *
173 * @param tokens The tokens to write to the stream.
174 * @throws IOException If there is an error writing to the stream.
175 */
176 public void writeTokens( List tokens ) throws IOException
177 {
178 writeTokens( tokens, 0, tokens.size() );
179 }
180 }