Use a helper class to process chained readers.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271518 13f79535-47bb-0310-9956-ffa450edef68

proposal/sandbox/filterreaders/src/main/org/apache/tools/ant/taskdefs/LoadFile.java

@@ -60,10 +60,9 @@ import org.apache.tools.ant.types.AntFilterReader;
 import org.apache.tools.ant.types.FilterReaderSet;
 import org.apache.tools.ant.types.Parameter;
 import org.apache.tools.ant.types.Parameterizable;
+import org.apache.tools.ant.util.ChainReaderHelper;
 
 import java.io.*;
-import java.lang.reflect.Constructor;
-import java.lang.reflect.InvocationTargetException;
 import java.util.Vector;
 
 /**
@@ -194,7 +193,12 @@ public final class LoadFile extends Task {
                 instream = new InputStreamReader(bis, encoding);
             }
 
-            String text = processStream(instream, size);
+            ChainReaderHelper crh = new ChainReaderHelper();
+            crh.setBufferSize(size);
+            crh.setPrimaryReader(instream);
+            crh.setFilterReaderSets(filterReaderSets);
+
+            String text = crh.processStream();
 
             if(evaluateProperties) {
                 text = project.replaceProperties(text);
@@ -229,79 +233,6 @@ public final class LoadFile extends Task {
         }
     }
 
-    /**
-     * Process the input by passing it through the reader chain.
-     */
-    private final String processStream(final Reader inputReader, final int size)
-        throws BuildException, IOException {
-
-        Reader instream = inputReader;
-        final char[] buffer = new char[size];
-        final int filterReadersCount = filterReaderSets.size();
-        final Vector finalFilters = new Vector();
-
-        for (int i = 0; i < filterReadersCount; i++) {
-            final FilterReaderSet filterset =
-                (FilterReaderSet) filterReaderSets.elementAt(i);
-            final Vector filterReaders = filterset.getFilterReaders();
-            final int readerCount = filterReaders.size();
-            for (int j = 0; j < readerCount; j++) {
-                final AntFilterReader afr =
-                    (AntFilterReader) filterReaders.elementAt(j);
-                finalFilters.addElement(afr);
-            }
-        }
-
-        final int filtersCount = finalFilters.size();
-
-        if (filtersCount > 0) {
-            for (int i = 0; i < filtersCount; i++) {
-                final AntFilterReader filter =
-                    (AntFilterReader) finalFilters.elementAt(i);
-                final String className = filter.getClassName();
-                if (className != null) {
-                    try {
-                        final Class clazz = Class.forName(className);
-                        if (clazz != null) {
-                            final Constructor[] constructors =
-                                clazz.getConstructors();
-                            final Reader[] rdr = {instream};
-                            instream =
-                                (Reader) constructors[0].newInstance(rdr);
-                            if (Parameterizable.class.isAssignableFrom(clazz)) {
-                                final Parameter[] params = filter.getParams();
-                                ((Parameterizable)
-                                    instream).setParameters(params);
-                            }
-                        }
-                    } catch (final ClassNotFoundException cnfe) {
-                        throw new BuildException(cnfe, location);
-                    } catch (final InstantiationException ie) {
-                        throw new BuildException(ie, location);
-                    } catch (final IllegalAccessException iae) {
-                        throw new BuildException(iae, location);
-                    } catch (final InvocationTargetException ite) {
-                        throw new BuildException(ite, location);
-                    }
-                }
-            }
-        }
-
-        int bufferLength = 0;
-        String text = null;
-        while (bufferLength != -1) {
-            bufferLength = instream.read(buffer);
-            if (bufferLength != -1) {
-                if (text == null) {
-                    text = new String(buffer, 0, bufferLength);
-                } else {
-                    text += new String(buffer, 0, bufferLength);
-                }
-            }
-        }
-        return text;
-    }
-
     /**
      * Add the FilterReaderSet element.
      */

proposal/sandbox/filterreaders/src/main/org/apache/tools/ant/taskdefs/LoadProperties.java

@@ -60,10 +60,9 @@ import org.apache.tools.ant.types.AntFilterReader;
 import org.apache.tools.ant.types.FilterReaderSet;
 import org.apache.tools.ant.types.Parameter;
 import org.apache.tools.ant.types.Parameterizable;
+import org.apache.tools.ant.util.ChainReaderHelper;
 
 import java.io.*;
-import java.lang.reflect.Constructor;
-import java.lang.reflect.InvocationTargetException;
 import java.util.Vector;
 
 /**
@@ -125,7 +124,12 @@ public final class LoadProperties extends Task {
             bis = new BufferedInputStream(fis);
             instream = new InputStreamReader(bis);
 
-            String text = processStream(instream, size);
+            ChainReaderHelper crh = new ChainReaderHelper();
+            crh.setBufferSize(size);
+            crh.setPrimaryReader(instream);
+            crh.setFilterReaderSets(filterReaderSets);
+
+            String text = crh.processStream();
             if (!text.endsWith("\n")) {
                 text = text + "\n";
             }
@@ -184,79 +188,6 @@ public final class LoadProperties extends Task {
         }
     }
 
-    /**
-     * Process the input by passing it through the reader chain.
-     */
-    private final String processStream(final Reader inputReader, final int size)
-        throws BuildException, IOException {
-
-        Reader instream = inputReader;
-        final char[] buffer = new char[size];
-        final int filterReadersCount = filterReaderSets.size();
-        final Vector finalFilters = new Vector();
-
-        for (int i = 0; i < filterReadersCount; i++) {
-            final FilterReaderSet filterset =
-                (FilterReaderSet) filterReaderSets.elementAt(i);
-            final Vector filterReaders = filterset.getFilterReaders();
-            final int readerCount = filterReaders.size();
-            for (int j = 0; j < readerCount; j++) {
-                final AntFilterReader afr =
-                    (AntFilterReader) filterReaders.elementAt(j);
-                finalFilters.addElement(afr);
-            }
-        }
-
-        final int filtersCount = finalFilters.size();
-
-        if (filtersCount > 0) {
-            for (int i = 0; i < filtersCount; i++) {
-                final AntFilterReader filter =
-                    (AntFilterReader) finalFilters.elementAt(i);
-                final String className = filter.getClassName();
-                if (className != null) {
-                    try {
-                        final Class clazz = Class.forName(className);
-                        if (clazz != null) {
-                            final Constructor[] constructors =
-                                clazz.getConstructors();
-                            final Reader[] rdr = {instream};
-                            instream =
-                                (Reader) constructors[0].newInstance(rdr);
-                            if (Parameterizable.class.isAssignableFrom(clazz)) {
-                                final Parameter[] params = filter.getParams();
-                                ((Parameterizable)
-                                    instream).setParameters(params);
-                            }
-                        }
-                    } catch (final ClassNotFoundException cnfe) {
-                        throw new BuildException(cnfe, location);
-                    } catch (final InstantiationException ie) {
-                        throw new BuildException(ie, location);
-                    } catch (final IllegalAccessException iae) {
-                        throw new BuildException(iae, location);
-                    } catch (final InvocationTargetException ite) {
-                        throw new BuildException(ite, location);
-                    }
-                }
-            }
-        }
-
-        int bufferLength = 0;
-        String text = null;
-        while (bufferLength != -1) {
-            bufferLength = instream.read(buffer);
-            if (bufferLength != -1) {
-                if (text == null) {
-                    text = new String(buffer, 0, bufferLength);
-                } else {
-                    text += new String(buffer, 0, bufferLength);
-                }
-            }
-        }
-        return text;
-    }
-
     /**
      * Add the FilterReaderSet element.
      */

proposal/sandbox/filterreaders/src/main/org/apache/tools/ant/util/ChainReaderHelper.java

@@ -0,0 +1,188 @@
+/*
+ *  The Apache Software License, Version 1.1
+ *
+ *  Copyright (c) 2002 The Apache Software Foundation.  All rights
+ *  reserved.
+ *
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions
+ *  are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright
+ *  notice, this list of conditions and the following disclaimer.
+ *
+ *  2. Redistributions in binary form must reproduce the above copyright
+ *  notice, this list of conditions and the following disclaimer in
+ *  the documentation and/or other materials provided with the
+ *  distribution.
+ *
+ *  3. The end-user documentation included with the redistribution, if
+ *  any, must include the following acknowlegement:
+ *  "This product includes software developed by the
+ *  Apache Software Foundation (http://www.apache.org/)."
+ *  Alternately, this acknowlegement may appear in the software itself,
+ *  if and wherever such third-party acknowlegements normally appear.
+ *
+ *  4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *  Foundation" must not be used to endorse or promote products derived
+ *  from this software without prior written permission. For written
+ *  permission, please contact apache@apache.org.
+ *
+ *  5. Products derived from this software may not be called "Apache"
+ *  nor may "Apache" appear in their names without prior written
+ *  permission of the Apache Group.
+ *
+ *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ *  DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ *  ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ *  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ *  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ *  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ *  SUCH DAMAGE.
+ *  ====================================================================
+ *
+ *  This software consists of voluntary contributions made by many
+ *  individuals on behalf of the Apache Software Foundation.  For more
+ *  information on the Apache Software Foundation, please see
+ *  <http://www.apache.org/>.
+ */
+package org.apache.tools.ant.util;
+
+import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.types.AntFilterReader;
+import org.apache.tools.ant.types.FilterReaderSet;
+import org.apache.tools.ant.types.Parameter;
+import org.apache.tools.ant.types.Parameterizable;
+
+import java.io.*;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.util.Vector;
+
+/**
+ * Process a FilterReader chain.
+ *
+ * @author <a href="mailto:umagesh@apache.org">Magesh Umasankar</a>
+ * @created 23 February 2002
+ */
+public final class ChainReaderHelper {
+
+    /**
+     * The primary reader to which the reader chain is to be attached.
+     */
+    public Reader primaryReader;
+
+    /**
+     * The size of the buffer to be used.
+     */
+    public int bufferSize = 4096;
+
+    /**
+     * Collection of 'FilterReaderSet's.
+     */
+    public Vector filterReaderSets = new Vector();
+
+    /**
+     * Sets the primary reader
+     */
+    public final void setPrimaryReader(Reader rdr) {
+        primaryReader = rdr;
+    }
+
+    /**
+     * Sets the buffer size to be used.  Defaults to 4096,
+     * if this method is not invoked.
+     */
+    public final void setBufferSize(int size) {
+        bufferSize = size;
+    }
+
+    /**
+     * Sets the collection of filter reader sets
+     */
+    public final void setFilterReaderSets(Vector frsets) {
+        filterReaderSets = frsets;
+    }
+
+    /**
+     * Process the reader chain
+     */
+    public final String processStream()
+        throws BuildException, IOException {
+
+        if (primaryReader == null) {
+            throw new BuildException("primaryReader must not be null.");
+        }
+
+        Reader instream = primaryReader;
+        final char[] buffer = new char[bufferSize];
+        final int filterReadersCount = filterReaderSets.size();
+        final Vector finalFilters = new Vector();
+
+        for (int i = 0; i < filterReadersCount; i++) {
+            final FilterReaderSet filterset =
+                (FilterReaderSet) filterReaderSets.elementAt(i);
+            final Vector filterReaders = filterset.getFilterReaders();
+            final int readerCount = filterReaders.size();
+            for (int j = 0; j < readerCount; j++) {
+                final AntFilterReader afr =
+                    (AntFilterReader) filterReaders.elementAt(j);
+                finalFilters.addElement(afr);
+            }
+        }
+
+        final int filtersCount = finalFilters.size();
+
+        if (filtersCount > 0) {
+            for (int i = 0; i < filtersCount; i++) {
+                final AntFilterReader filter =
+                    (AntFilterReader) finalFilters.elementAt(i);
+                final String className = filter.getClassName();
+                if (className != null) {
+                    try {
+                        final Class clazz = Class.forName(className);
+                        if (clazz != null) {
+                            final Constructor[] constructors =
+                                clazz.getConstructors();
+                            final Reader[] rdr = {instream};
+                            instream =
+                                (Reader) constructors[0].newInstance(rdr);
+                            if (Parameterizable.class.isAssignableFrom(clazz)) {
+                                final Parameter[] params = filter.getParams();
+                                ((Parameterizable)
+                                    instream).setParameters(params);
+                            }
+                        }
+                    } catch (final ClassNotFoundException cnfe) {
+                        throw new BuildException(cnfe);
+                    } catch (final InstantiationException ie) {
+                        throw new BuildException(ie);
+                    } catch (final IllegalAccessException iae) {
+                        throw new BuildException(iae);
+                    } catch (final InvocationTargetException ite) {
+                        throw new BuildException(ite);
+                    }
+                }
+            }
+        }
+
+        int bufferLength = 0;
+        String text = null;
+        while (bufferLength != -1) {
+            bufferLength = instream.read(buffer);
+            if (bufferLength != -1) {
+                if (text == null) {
+                    text = new String(buffer, 0, bufferLength);
+                } else {
+                    text += new String(buffer, 0, bufferLength);
+                }
+            }
+        }
+        return text;
+    }
+}