jni: Add Java interfaces to fz_stream and fz_output types.

This will allow us to read and write documents using I/O written
in Java, exposed by SeekableInputStream and SeekableOutputStream.

We supply an example FileStream which implements seekable streams
backed by a RandomAccessFile.

6 files changed, 86 insertions, 0 deletions

diff --git a/platform/java/src/com/artifex/mupdf/fitz/Document.java b/platform/java/src/com/artifex/mupdf/fitz/Document.java
index 9b512c89..0da94d87 100644
--- a/platform/java/src/com/artifex/mupdf/fitz/Document.java
+++ b/platform/java/src/com/artifex/mupdf/fitz/Document.java
@@ -27,6 +27,7 @@ public class Document
 
 	protected native static Document openNativeWithPath(String filename);
 	protected native static Document openNativeWithBuffer(byte buffer[], String magic);
+	protected native static Document openNativeWithStream(SeekableInputStream stream, String mimeType);
 
 	public static Document openDocument(String filename) {
 		Document doc = openNativeWithPath(filename);
@@ -38,6 +39,10 @@ public class Document
 		return openNativeWithBuffer(buffer, magic);
 	}
 
+	public static Document openDocument(SeekableInputStream stream, String magic) {
+		return openNativeWithStream(stream, magic);
+	}
+
 	public static native boolean recognize(String magic);
 
 	public native boolean needsPassword();
diff --git a/platform/java/src/com/artifex/mupdf/fitz/FileStream.java b/platform/java/src/com/artifex/mupdf/fitz/FileStream.java
new file mode 100644
index 00000000..3d9ad0d3
--- /dev/null
+++ b/platform/java/src/com/artifex/mupdf/fitz/FileStream.java
@@ -0,0 +1,43 @@
+package com.artifex.mupdf.fitz;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+public class FileStream implements SeekableInputStream, SeekableOutputStream
+{
+	protected RandomAccessFile file;
+
+	public FileStream(String path, String mode) throws IOException {
+		file = new RandomAccessFile(path, mode);
+	}
+
+	public FileStream(File path, String mode) throws IOException {
+		file = new RandomAccessFile(path, mode);
+	}
+
+	public int read(byte[] buf) throws IOException {
+		return file.read(buf);
+	}
+
+	public void write(byte[] buf, int off, int len) throws IOException {
+		file.write(buf, off, len);
+	}
+
+	public long seek(long offset, int whence) throws IOException {
+		switch (whence) {
+		case SEEK_SET: file.seek(offset); break;
+		case SEEK_CUR: file.seek(file.getFilePointer() + offset); break;
+		case SEEK_END: file.seek(file.length() + offset); break;
+		}
+		return file.getFilePointer();
+	}
+
+	public long position() throws IOException {
+		return file.getFilePointer();
+	}
+
+	public void close() throws IOException {
+		file.close();
+	}
+}
diff --git a/platform/java/src/com/artifex/mupdf/fitz/PDFDocument.java b/platform/java/src/com/artifex/mupdf/fitz/PDFDocument.java
index 68835aaa..945294f3 100644
--- a/platform/java/src/com/artifex/mupdf/fitz/PDFDocument.java
+++ b/platform/java/src/com/artifex/mupdf/fitz/PDFDocument.java
@@ -100,5 +100,11 @@ public class PDFDocument extends Document
 	public native PDFObject addFont(Font font);
 	public native boolean hasUnsavedChanges();
 	public native boolean canBeSavedIncrementally();
+
 	public native int save(String filename, String options);
+
+	protected native int nativeSaveWithStream(SeekableOutputStream stream, String options);
+	public int save(SeekableOutputStream stream, String options) {
+		return nativeSaveWithStream(stream, options);
+	}
 }
diff --git a/platform/java/src/com/artifex/mupdf/fitz/SeekableInputStream.java b/platform/java/src/com/artifex/mupdf/fitz/SeekableInputStream.java
new file mode 100644
index 00000000..74b1a185
--- /dev/null
+++ b/platform/java/src/com/artifex/mupdf/fitz/SeekableInputStream.java
@@ -0,0 +1,9 @@
+package com.artifex.mupdf.fitz;
+
+import java.io.IOException;
+
+public interface SeekableInputStream extends SeekableStream
+{
+	/* Behaves like java.io.InputStream.read */
+	int read(byte[] b) throws IOException;
+}
diff --git a/platform/java/src/com/artifex/mupdf/fitz/SeekableOutputStream.java b/platform/java/src/com/artifex/mupdf/fitz/SeekableOutputStream.java
new file mode 100644
index 00000000..d22ba996
--- /dev/null
+++ b/platform/java/src/com/artifex/mupdf/fitz/SeekableOutputStream.java
@@ -0,0 +1,9 @@
+package com.artifex.mupdf.fitz;
+
+import java.io.IOException;
+
+public interface SeekableOutputStream extends SeekableStream
+{
+	/* Behaves like java.io.OutputStream.write */
+	void write(byte[] b, int off, int len) throws IOException;
+}
diff --git a/platform/java/src/com/artifex/mupdf/fitz/SeekableStream.java b/platform/java/src/com/artifex/mupdf/fitz/SeekableStream.java
new file mode 100644
index 00000000..83f79ea2
--- /dev/null
+++ b/platform/java/src/com/artifex/mupdf/fitz/SeekableStream.java
@@ -0,0 +1,14 @@
+package com.artifex.mupdf.fitz;
+
+import java.io.IOException;
+
+public interface SeekableStream
+{
+	int SEEK_SET = 0; /* set file position to offset */
+	int SEEK_CUR = 1; /* set file position to current location plus offset */
+	int SEEK_END = 2; /* set file position to EOF plus offset */
+
+	long seek(long offset, int whence) throws IOException;
+	long position() throws IOException;
+	void close() throws IOException;
+}