org.argeo.slc.core/src/org/argeo/slc/core/execution/SedFilteredResource.java

   1 /*
   2  * Copyright (C) 2007-2012 Argeo GmbH
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.argeo.slc.core.execution;
  17
  18 import java.io.File;
  19 import java.io.FileInputStream;
  20 import java.io.IOException;
  21 import java.nio.ByteBuffer;
  22 import java.nio.CharBuffer;
  23 import java.nio.channels.FileChannel;
  24 import java.nio.charset.Charset;
  25 import java.nio.charset.CharsetDecoder;
  26 import java.util.ArrayList;
  27 import java.util.HashMap;
  28 import java.util.List;
  29 import java.util.Map;
  30 import java.util.StringTokenizer;
  31 import java.util.regex.Matcher;
  32 import java.util.regex.Pattern;
  33
  34 import org.apache.commons.io.IOUtils;
  35 import org.argeo.slc.SlcException;
  36 import org.springframework.beans.factory.FactoryBean;
  37 import org.springframework.beans.factory.InitializingBean;
  38 import org.springframework.core.io.ByteArrayResource;
  39 import org.springframework.core.io.Resource;
  40
  41 /** Experimental and suboptimal */
  42 public class SedFilteredResource implements FactoryBean<Resource>,
  43                 InitializingBean {
  44         private Resource source;
  45
  46         private List<String> filters = new ArrayList<String>();
  47         private Map<Pattern, String> patterns = new HashMap<Pattern, String>();
  48
  49         private String charset = "UTF-8";
  50         private Charset cs;
  51         private CharsetDecoder decoder;
  52
  53         // private CharsetEncoder encoder;
  54
  55         public Resource getObject() throws Exception {
  56                 if (filters.size() == 0)
  57                         return source;
  58
  59                 // int capacity = 100 * 1024;// 100 KB
  60                 ByteBuffer bb;
  61                 if (source instanceof ByteArrayResource) {
  62                         bb = ByteBuffer.wrap(((ByteArrayResource) source).getByteArray());
  63                 } else {
  64                         FileInputStream fis = null;
  65                         try {
  66                                 File file = source.getFile();
  67                                 fis = new FileInputStream(file);
  68                                 FileChannel fc = fis.getChannel();
  69
  70                                 // Get the file's size and then map it into memory
  71                                 int sz = (int) fc.size();
  72                                 bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, sz);
  73                         } catch (IOException e) {
  74                                 // ReadableByteChannel channel = Channels.newChannel(source
  75                                 // .getInputStream());
  76                                 // bb = ByteBuffer.allocateDirect(capacity);
  77                                 // int read = 0;
  78                                 // do {
  79                                 // read = channel.read(bb);
  80                                 // } while (read > 0);
  81                                 // FIXME : use nio to parse the stream as it goes
  82                                 bb = ByteBuffer.wrap(IOUtils.toByteArray(source
  83                                                 .getInputStream()));
  84                         } finally {
  85                                 IOUtils.closeQuietly(fis);
  86                         }
  87                 }
  88                 CharBuffer cb = decoder.decode(bb);
  89                 for (Pattern pattern : patterns.keySet()) {
  90                         Matcher matcher = pattern.matcher(cb);
  91                         String output = matcher.replaceAll(patterns.get(pattern));
  92                         cb = CharBuffer.wrap(output);
  93                 }
  94                 // ByteBuffer bbout = encoder.encode(cb);
  95                 // ByteArrayOutputStream out = new ByteArrayOutputStream(capacity);
  96                 // WritableByteChannel wchannel = Channels.newChannel(out);
  97                 // wchannel.write(bbout);
  98                 ByteArrayResource res = new ByteArrayResource(cb.toString().getBytes());
  99                 return res;
 100         }
 101
 102         public Class<?> getObjectType() {
 103                 return Resource.class;
 104         }
 105
 106         public boolean isSingleton() {
 107                 return true;
 108         }
 109
 110         public void afterPropertiesSet() throws Exception {
 111                 cs = Charset.forName(charset);
 112                 decoder = cs.newDecoder();
 113                 // encoder = cs.newEncoder();
 114
 115                 for (String sedStr : filters) {
 116                         sedStr = sedStr.trim();
 117                         if (sedStr.length() < 4)
 118                                 throw new SlcException(sedStr + " not properly formatted.");
 119                         if (sedStr.charAt(0) != 's')
 120                                 throw new SlcException(sedStr + " not properly formatted.");
 121                         Character sep = sedStr.charAt(1);
 122                         List<String> tokens = new ArrayList<String>(4);
 123                         StringTokenizer st = new StringTokenizer(sedStr, sep.toString());
 124                         while (st.hasMoreTokens())
 125                                 tokens.add(st.nextToken());
 126                         if (tokens.size() != 3 && tokens.size() != 4)
 127                                 throw new SlcException(sedStr + " not properly formatted.");
 128                         patterns.put(Pattern.compile(tokens.get(1)), tokens.get(2));
 129                 }
 130         }
 131
 132         public void setSource(Resource source) {
 133                 this.source = source;
 134         }
 135
 136         public void setFilters(List<String> filters) {
 137                 this.filters = filters;
 138         }
 139
 140         public void setCharset(String charset) {
 141                 this.charset = charset;
 142         }
 143
 144 }