now mostly streamified!
[nikiroo-utils.git] / src / be / nikiroo / utils / serial / Importer.java
index bca157c501bcb8a512fd5367585b15a06a82771e..2608db272bf85373b0fcecda52aa8e76563b904c 100644 (file)
@@ -1,12 +1,17 @@
 package be.nikiroo.utils.serial;
 
 import java.io.IOException;
-import java.io.UnsupportedEncodingException;
+import java.io.InputStream;
 import java.lang.reflect.Field;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.zip.GZIPInputStream;
 
-import be.nikiroo.utils.StringUtils;
+import be.nikiroo.utils.IOUtils;
+import be.nikiroo.utils.streams.Base64InputStream;
+import be.nikiroo.utils.streams.BufferedInputStream;
+import be.nikiroo.utils.streams.NextableInputStream;
+import be.nikiroo.utils.streams.NextableInputStreamStep;
 
 /**
  * A simple class that can accept the output of {@link Exporter} to recreate
@@ -19,9 +24,6 @@ import be.nikiroo.utils.StringUtils;
  * @author niki
  */
 public class Importer {
-       static private Integer SIZE_ID = null;
-       static private byte[] NEWLINE = null;
-
        private Boolean link;
        private Object me;
        private Importer child;
@@ -29,15 +31,6 @@ public class Importer {
 
        private String currentFieldName;
 
-       static {
-               try {
-                       SIZE_ID = "EXT:".getBytes("UTF-8").length;
-                       NEWLINE = "\n".getBytes("UTF-8");
-               } catch (UnsupportedEncodingException e) {
-                       // UTF-8 is mandated to exist on confirming jre's
-               }
-       }
-
        /**
         * Create a new {@link Importer}.
         */
@@ -55,7 +48,7 @@ public class Importer {
         * content, or a number of lines of it (any given line <b>MUST</b> be
         * complete though) and accumulate it with the already present data.
         * 
-        * @param data
+        * @param in
         *            the data to parse
         * 
         * @return itself so it can be chained
@@ -70,77 +63,55 @@ public class Importer {
         *             if a class described in the serialised data cannot be found
         * @throws IOException
         *             if the content cannot be read (for instance, corrupt data)
+        * @throws NullPointerException
+        *             if the stream is empty
         */
-       public Importer read(String data) throws NoSuchFieldException,
-                       NoSuchMethodException, ClassNotFoundException, IOException {
-               return read(data.getBytes("UTF-8"), 0);
-       }
+       public Importer read(InputStream in) throws NoSuchFieldException,
+                       NoSuchMethodException, ClassNotFoundException, IOException,
+                       NullPointerException {
 
-       /**
-        * Read some data into this {@link Importer}: it can be the full serialised
-        * content, or a number of lines of it (any given line <b>MUST</b> be
-        * complete though) and accumulate it with the already present data.
-        * 
-        * @param data
-        *            the data to parse
-        * @param offset
-        *            the offset at which to start reading the data (we ignore
-        *            anything that goes before that offset)
-        * 
-        * @return itself so it can be chained
-        * 
-        * @throws NoSuchFieldException
-        *             if the serialised data contains information about a field
-        *             which does actually not exist in the class we know of
-        * @throws NoSuchMethodException
-        *             if a class described in the serialised data cannot be created
-        *             because it is not compatible with this code
-        * @throws ClassNotFoundException
-        *             if a class described in the serialised data cannot be found
-        * @throws IOException
-        *             if the content cannot be read (for instance, corrupt data)
-        */
-       private Importer read(byte[] data, int offset) throws NoSuchFieldException,
-                       NoSuchMethodException, ClassNotFoundException, IOException {
-
-               int dataStart = offset;
-               while (dataStart < data.length) {
-                       String id = "";
-                       if (data.length - dataStart >= SIZE_ID) {
-                               id = new String(data, dataStart, SIZE_ID);
-                       }
+               NextableInputStream stream = new NextableInputStream(in,
+                               new NextableInputStreamStep('\n'));
 
-                       boolean zip = id.equals("ZIP:");
-                       boolean b64 = id.equals("B64:");
-                       if (zip || b64) {
-                               dataStart += SIZE_ID;
+               try {
+                       if (in == null) {
+                               throw new NullPointerException("InputStream is null");
                        }
 
-                       int count = find(data, dataStart, NEWLINE);
-                       count -= dataStart;
-                       if (count < 0) {
-                               count = data.length - dataStart;
-                       }
+                       boolean first = true;
+                       while (stream.next()) {
+                               if (stream.eof()) {
+                                       if (first) {
+                                               throw new NullPointerException(
+                                                               "InputStream empty, normal termination");
+                                       }
+                                       return this;
+                               }
+                               first = false;
+
+                               boolean zip = stream.startsWith("ZIP:");
+                               boolean b64 = stream.startsWith("B64:");
+
+                               if (zip || b64) {
+                                       stream.skip("XXX:".length());
+
+                                       InputStream decoded = stream.open();
+                                       if (zip) {
+                                               decoded = new GZIPInputStream(decoded);
+                                       }
+                                       decoded = new Base64InputStream(decoded, false);
 
-                       if (zip || b64) {
-                               boolean unpacked = false;
-                               try {
-                                       byte[] line = StringUtils.unbase64(data, dataStart, count,
-                                                       zip);
-                                       unpacked = true;
-                                       read(line, 0);
-                               } catch (IOException e) {
-                                       throw new IOException("Internal error when decoding "
-                                                       + (unpacked ? "unpacked " : "")
-                                                       + (zip ? "ZIP" : "B64")
-                                                       + " content: input may be corrupt");
+                                       try {
+                                               read(decoded);
+                                       } finally {
+                                               decoded.close();
+                                       }
+                               } else {
+                                       processLine(stream);
                                }
-                       } else {
-                               String line = new String(data, dataStart, count, "UTF-8");
-                               processLine(line);
                        }
-
-                       dataStart += count + NEWLINE.length;
+               } finally {
+                       stream.close(false);
                }
 
                return this;
@@ -150,7 +121,7 @@ public class Importer {
         * Read a single (whole) line of serialised data into this {@link Importer}
         * and accumulate it with the already present data.
         * 
-        * @param line
+        * @param in
         *            the line to parse
         * 
         * @return TRUE if we are just done with one object or sub-object
@@ -166,11 +137,13 @@ public class Importer {
         * @throws IOException
         *             if the content cannot be read (for instance, corrupt data)
         */
-       private boolean processLine(String line) throws NoSuchFieldException,
-                       NoSuchMethodException, ClassNotFoundException, IOException {
+       private boolean processLine(BufferedInputStream in)
+                       throws NoSuchFieldException, NoSuchMethodException,
+                       ClassNotFoundException, IOException {
+
                // Defer to latest child if any
                if (child != null) {
-                       if (child.processLine(line)) {
+                       if (child.processLine(in)) {
                                if (currentFieldName != null) {
                                        setField(currentFieldName, child.getValue());
                                        currentFieldName = null;
@@ -181,59 +154,108 @@ public class Importer {
                        return false;
                }
 
-               if (line.equals("{")) { // START: new child if needed
+               // Start/Stop object
+               if (in.is("{")) { // START: new child if needed
                        if (link != null) {
                                child = new Importer(map);
                        }
-               } else if (line.equals("}")) { // STOP: report self to parent
+                       in.end();
+                       return false;
+               } else if (in.is("}")) { // STOP: report self to parent
+                       in.end();
                        return true;
-               } else if (line.startsWith("REF ")) { // REF: create/link self
-                       String[] tab = line.substring("REF ".length()).split("@");
-                       String type = tab[0];
-                       tab = tab[1].split(":");
-                       String ref = tab[0];
-
-                       link = map.containsKey(ref);
-                       if (link) {
-                               me = map.get(ref);
-                       } else {
-                               if (line.endsWith(":")) {
-                                       // construct
-                                       me = SerialUtils.createObject(type);
+               }
+
+               // Custom objects
+               if (CustomSerializer.isCustom(in)) {
+                       // not a field value but a direct value
+                       me = SerialUtils.decode(in);
+                       return false;
+               }
+
+               // REF: (object)
+               if (in.startsWith("REF ")) { // REF: create/link self
+                       // here, line is REF type@999:xxx
+                       // xxx is optional
+
+                       NextableInputStream stream = new NextableInputStream(in,
+                                       new NextableInputStreamStep(':'));
+                       try {
+                               stream.next();
+
+                               stream.skip("REF ".length());
+                               String header = IOUtils.readSmallStream(stream);
+
+                               String[] tab = header.split("@");
+                               if (tab.length != 2) {
+                                       throw new IOException("Bad import header line: " + header);
+                               }
+                               String type = tab[0];
+                               String ref = tab[1];
+
+                               stream.nextAll();
+
+                               link = map.containsKey(ref);
+                               if (link) {
+                                       me = map.get(ref);
+                                       stream.end();
                                } else {
-                                       // direct value
-                                       int pos = line.indexOf(":");
-                                       String encodedValue = line.substring(pos + 1);
-                                       me = SerialUtils.decode(encodedValue);
+                                       if (stream.eof()) {
+                                               // construct
+                                               me = SerialUtils.createObject(type);
+                                       } else {
+                                               // direct value
+                                               me = SerialUtils.decode(stream);
+                                       }
+                                       map.put(ref, me);
                                }
-                               map.put(ref, me);
+                       } finally {
+                               stream.close(false);
                        }
-               } else { // FIELD: new field *or* direct simple value
-                       if (line.endsWith(":")) {
-                               // field value is compound
-                               currentFieldName = line.substring(0, line.length() - 1);
-                       } else if (line.startsWith(":") || !line.contains(":")
-                                       || line.startsWith("\"") || CustomSerializer.isCustom(line)) {
-                               // not a field value but a direct value
-                               me = SerialUtils.decode(line);
-                       } else {
-                               // field value is direct
-                               int pos = line.indexOf(":");
-                               String fieldName = line.substring(0, pos);
-                               String encodedValue = line.substring(pos + 1);
-                               Object value = null;
-                               value = SerialUtils.decode(encodedValue);
-
-                               // To support simple types directly:
-                               if (me == null) {
-                                       me = value;
+
+                       return false;
+               }
+
+               if (SerialUtils.isDirectValue(in)) {
+                       // not a field value but a direct value
+                       me = SerialUtils.decode(in);
+                       return false;
+               }
+
+               if (in.startsWith("^")) {
+                       in.skip(1);
+
+                       NextableInputStream nameThenContent = new NextableInputStream(in,
+                                       new NextableInputStreamStep(':'));
+
+                       try {
+                               nameThenContent.next();
+                               String fieldName = IOUtils.readSmallStream(nameThenContent);
+
+                               if (nameThenContent.next() && !nameThenContent.eof()) {
+                                       // field value is direct or custom
+                                       Object value = null;
+                                       value = SerialUtils.decode(nameThenContent);
+
+                                       // To support simple types directly:
+                                       if (me == null) {
+                                               me = value;
+                                       } else {
+                                               setField(fieldName, value);
+                                       }
                                } else {
-                                       setField(fieldName, value);
+                                       // field value is compound
+                                       currentFieldName = fieldName;
                                }
+                       } finally {
+                               nameThenContent.close(false);
                        }
+
+                       return false;
                }
 
-               return false;
+               String line = IOUtils.readSmallStream(in);
+               throw new IOException("Line cannot be processed: <" + line + ">");
        }
 
        private void setField(String name, Object value)
@@ -255,37 +277,6 @@ public class Importer {
                }
        }
 
-       /**
-        * Find the given needle in the data and return its position (or -1 if not
-        * found).
-        * 
-        * @param data
-        *            the data to look through
-        * @param offset
-        *            the offset at wich to start searching
-        * @param needle
-        *            the needle to find
-        * 
-        * @return the position of the needle if found, -1 if not found
-        */
-       private int find(byte[] data, int offset, byte[] needle) {
-               for (int i = offset; i + needle.length - 1 < data.length; i++) {
-                       boolean same = true;
-                       for (int j = 0; j < needle.length; j++) {
-                               if (data[i + j] != needle[j]) {
-                                       same = false;
-                                       break;
-                               }
-                       }
-
-                       if (same) {
-                               return i;
-                       }
-               }
-
-               return -1;
-       }
-
        /**
         * Return the current deserialised value.
         *