Extract positional XML parser into common and fix encoding issues

The XML DOM parser used by the lint CLI driver (which tracks
positions) is needed outside of lint, so pull it out of the lint/cli
project, and refactor it such that it does not directly reference the
lint Position APIs (but can utilize them when subclassed in lint).

In addition, handle non-UTF-8 file encodings. XML files can be encoded
in other character sets, and can specify this via the encoding
attribute in the XML prologue. Until now, the CLI lint runner would
just read the XML file contents in using the default encoding and
parse this. Now there's a new utility method which takes a byte[] and
infers the desired encoding and uses that to convert the byte[] into a
string using the correct encoding. (We can't just pass an InputStream
and let the SAX parser handle this on its own because the XML parser
needs to access the character stream in order to assign correct node
offsets.)  This code now also handles the byte order mark more
cleanly.

There are some new unit tests too to check the new encoding, BOM and
offset handling.

Change-Id: Ib0badbbe72172e3408c6d5af2413be51280a7724

2 files changed, 15 insertions, 0 deletions

diff --git a/common/src/com/android/io/FileWrapper.java b/common/src/com/android/io/FileWrapper.java
index 2859c0d..84a1f3e 100644
--- a/common/src/com/android/io/FileWrapper.java
+++ b/common/src/com/android/io/FileWrapper.java
@@ -85,6 +85,7 @@ public class FileWrapper extends File implements IAbstractFile {
         super(uri);
     }
 
+    @Override
     public InputStream getContents() throws StreamException {
         try {
             return new FileInputStream(this);
@@ -93,6 +94,7 @@ public class FileWrapper extends File implements IAbstractFile {
         }
     }
 
+    @Override
     public void setContents(InputStream source) throws StreamException {
         FileOutputStream fos = null;
         try {
@@ -116,6 +118,7 @@ public class FileWrapper extends File implements IAbstractFile {
         }
     }
 
+    @Override
     public OutputStream getOutputStream() throws StreamException {
         try {
             return new FileOutputStream(this);
@@ -124,10 +127,12 @@ public class FileWrapper extends File implements IAbstractFile {
         }
     }
 
+    @Override
     public PreferredWriteMode getPreferredWriteMode() {
         return PreferredWriteMode.OUTPUTSTREAM;
     }
 
+    @Override
     public String getOsLocation() {
         return getAbsolutePath();
     }
@@ -137,10 +142,12 @@ public class FileWrapper extends File implements IAbstractFile {
         return isFile();
     }
 
+    @Override
     public long getModificationStamp() {
         return lastModified();
     }
 
+    @Override
     public IAbstractFolder getParentFolder() {
         String p = this.getParent();
         if (p == null) {
diff --git a/common/src/com/android/io/FolderWrapper.java b/common/src/com/android/io/FolderWrapper.java
index 26ed9cf..c29c934 100644
--- a/common/src/com/android/io/FolderWrapper.java
+++ b/common/src/com/android/io/FolderWrapper.java
@@ -81,6 +81,7 @@ public class FolderWrapper extends File implements IAbstractFolder {
         super(file.getAbsolutePath());
     }
 
+    @Override
     public IAbstractResource[] listMembers() {
         File[] files = listFiles();
         final int count = files == null ? 0 : files.length;
@@ -100,8 +101,10 @@ public class FolderWrapper extends File implements IAbstractFolder {
         return afiles;
     }
 
+    @Override
     public boolean hasFile(final String name) {
         String[] match = list(new FilenameFilter() {
+            @Override
             public boolean accept(IAbstractFolder dir, String filename) {
                 return name.equals(filename);
             }
@@ -110,14 +113,17 @@ public class FolderWrapper extends File implements IAbstractFolder {
         return match.length > 0;
     }
 
+    @Override
     public IAbstractFile getFile(String name) {
         return new FileWrapper(this, name);
     }
 
+    @Override
     public IAbstractFolder getFolder(String name) {
         return new FolderWrapper(this, name);
     }
 
+    @Override
     public IAbstractFolder getParentFolder() {
         String p = this.getParent();
         if (p == null) {
@@ -126,6 +132,7 @@ public class FolderWrapper extends File implements IAbstractFolder {
         return new FolderWrapper(p);
     }
 
+    @Override
     public String getOsLocation() {
         return getAbsolutePath();
     }
@@ -135,6 +142,7 @@ public class FolderWrapper extends File implements IAbstractFolder {
         return isDirectory();
     }
 
+    @Override
     public String[] list(FilenameFilter filter) {
         File[] files = listFiles();
         if (files != null && files.length > 0) {