runtime/org.argeo.slc.core/src/main/java/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, InitializingBean {
  43         private Resource source;
  44
  45         private List<String> filters = new ArrayList<String>();
  46         private Map<Pattern, String> patterns = new HashMap<Pattern, String>();
  47
  48         private String charset = "UTF-8";
  49         private Charset cs;
  50         private CharsetDecoder decoder;
  51
  52         // private CharsetEncoder encoder;
  53
  54         public Object getObject() throws Exception {
  55                 if (filters.size() == 0)
  56                         return source;
  57
  58                 // int capacity = 100 * 1024;// 100 KB
  59                 ByteBuffer bb;
  60                 if (source instanceof ByteArrayResource) {
  61                         bb = ByteBuffer.wrap(((ByteArrayResource) source).getByteArray());
  62                 } else {
  63                         FileInputStream fis = null;
  64                         try {
  65                                 File file = source.getFile();
  66                                 fis = new FileInputStream(file);
  67                                 FileChannel fc = fis.getChannel();
  68
  69                                 // Get the file's size and then map it into memory
  70                                 int sz = (int) fc.size();
  71                                 bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, sz);
  72                         } catch (IOException e) {
  73                                 // ReadableByteChannel channel = Channels.newChannel(source
  74                                 // .getInputStream());
  75                                 // bb = ByteBuffer.allocateDirect(capacity);
  76                                 // int read = 0;
  77                                 // do {
  78                                 // read = channel.read(bb);
  79                                 // } while (read > 0);
  80                                 // FIXME : use nio to parse the stream as it goes
  81                                 bb = ByteBuffer.wrap(IOUtils.toByteArray(source
  82                                                 .getInputStream()));
  83                         } finally {
  84                                 IOUtils.closeQuietly(fis);
  85                         }
  86                 }
  87                 CharBuffer cb = decoder.decode(bb);
  88                 for (Pattern pattern : patterns.keySet()) {
  89                         Matcher matcher = pattern.matcher(cb);
  90                         String output = matcher.replaceAll(patterns.get(pattern));
  91                         cb = CharBuffer.wrap(output);
  92                 }
  93                 // ByteBuffer bbout = encoder.encode(cb);
  94                 // ByteArrayOutputStream out = new ByteArrayOutputStream(capacity);
  95                 // WritableByteChannel wchannel = Channels.newChannel(out);
  96                 // wchannel.write(bbout);
  97                 ByteArrayResource res = new ByteArrayResource(cb.toString().getBytes());
  98                 return res;
  99         }
 100
 101         public Class<?> getObjectType() {
 102                 return Resource.class;
 103         }
 104
 105         public boolean isSingleton() {
 106                 return true;
 107         }
 108
 109         public void afterPropertiesSet() throws Exception {
 110                 cs = Charset.forName(charset);
 111                 decoder = cs.newDecoder();
 112                 // encoder = cs.newEncoder();
 113
 114                 for (String sedStr : filters) {
 115                         sedStr = sedStr.trim();
 116                         if (sedStr.length() < 4)
 117                                 throw new SlcException(sedStr + " not properly formatted.");
 118                         if (sedStr.charAt(0) != 's')
 119                                 throw new SlcException(sedStr + " not properly formatted.");
 120                         Character sep = sedStr.charAt(1);
 121                         List<String> tokens = new ArrayList<String>(4);
 122                         StringTokenizer st = new StringTokenizer(sedStr, sep.toString());
 123                         while (st.hasMoreTokens())
 124                                 tokens.add(st.nextToken());
 125                         if (tokens.size() != 3 && tokens.size() != 4)
 126                                 throw new SlcException(sedStr + " not properly formatted.");
 127                         patterns.put(Pattern.compile(tokens.get(1)), tokens.get(2));
 128                 }
 129         }
 130
 131         public void setSource(Resource source) {
 132                 this.source = source;
 133         }
 134
 135         public void setFilters(List<String> filters) {
 136                 this.filters = filters;
 137         }
 138
 139         public void setCharset(String charset) {
 140                 this.charset = charset;
 141         }
 142
 143 }