Change package name

src/main/java/gitbucket/core/util/PatchUtil.java

@@ -0,0 +1,93 @@
+package gitbucket.core.util;
+
+import org.eclipse.jgit.api.errors.PatchApplyException;
+import org.eclipse.jgit.diff.RawText;
+import org.eclipse.jgit.internal.JGitText;
+import org.eclipse.jgit.patch.FileHeader;
+import org.eclipse.jgit.patch.HunkHeader;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.text.MessageFormat;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * This class helps to apply patch. Most of these code came from {@link org.eclipse.jgit.api.ApplyCommand}.
+ */
+public class PatchUtil {
+
+    public static String apply(String source, String patch, FileHeader fh)
+            throws IOException, PatchApplyException {
+        RawText rt = new RawText(source.getBytes("UTF-8"));
+        List<String> oldLines = new ArrayList<String>(rt.size());
+        for (int i = 0; i < rt.size(); i++)
+            oldLines.add(rt.getString(i));
+        List<String> newLines = new ArrayList<String>(oldLines);
+        for (HunkHeader hh : fh.getHunks()) {
+            ByteArrayOutputStream out = new ByteArrayOutputStream();
+            out.write(patch.getBytes("UTF-8"), hh.getStartOffset(), hh.getEndOffset() - hh.getStartOffset());
+            RawText hrt = new RawText(out.toByteArray());
+            List<String> hunkLines = new ArrayList<String>(hrt.size());
+            for (int i = 0; i < hrt.size(); i++)
+                hunkLines.add(hrt.getString(i));
+            int pos = 0;
+            for (int j = 1; j < hunkLines.size(); j++) {
+                String hunkLine = hunkLines.get(j);
+                switch (hunkLine.charAt(0)) {
+                    case ' ':
+                        if (!newLines.get(hh.getNewStartLine() - 1 + pos).equals(
+                                hunkLine.substring(1))) {
+                            throw new PatchApplyException(MessageFormat.format(
+                                    JGitText.get().patchApplyException, hh));
+                        }
+                        pos++;
+                        break;
+                    case '-':
+                        if (!newLines.get(hh.getNewStartLine() - 1 + pos).equals(
+                                hunkLine.substring(1))) {
+                            throw new PatchApplyException(MessageFormat.format(
+                                    JGitText.get().patchApplyException, hh));
+                        }
+                        newLines.remove(hh.getNewStartLine() - 1 + pos);
+                        break;
+                    case '+':
+                        newLines.add(hh.getNewStartLine() - 1 + pos,
+                                hunkLine.substring(1));
+                        pos++;
+                        break;
+                }
+            }
+        }
+        if (!isNoNewlineAtEndOfFile(fh))
+            newLines.add(""); //$NON-NLS-1$
+        if (!rt.isMissingNewlineAtEnd())
+            oldLines.add(""); //$NON-NLS-1$
+        if (!isChanged(oldLines, newLines))
+            return null; // don't touch the file
+        StringBuilder sb = new StringBuilder();
+        for (String l : newLines) {
+            // don't bother handling line endings - if it was windows, the \r is
+            // still there!
+            sb.append(l).append('\n');
+        }
+        sb.deleteCharAt(sb.length() - 1);
+        return sb.toString();
+    }
+
+    private static boolean isChanged(List<String> ol, List<String> nl) {
+        if (ol.size() != nl.size())
+            return true;
+        for (int i = 0; i < ol.size(); i++)
+            if (!ol.get(i).equals(nl.get(i)))
+                return true;
+        return false;
+    }
+
+    private static boolean isNoNewlineAtEndOfFile(FileHeader fh) {
+        HunkHeader lastHunk = fh.getHunks().get(fh.getHunks().size() - 1);
+        RawText lhrt = new RawText(lastHunk.getBuffer());
+        return lhrt.getString(lhrt.size() - 1).equals(
+                "\\ No newline at end of file"); //$NON-NLS-1$
+    }
+}