diff --git a/src/com/github/jabbalaci/graphviz/GraphViz.java b/src/com/github/jabbalaci/graphviz/GraphViz.java
index 5e3893b..aa2e017 100644
--- a/src/com/github/jabbalaci/graphviz/GraphViz.java
+++ b/src/com/github/jabbalaci/graphviz/GraphViz.java
@@ -25,13 +25,11 @@
  ******************************************************************************
  */
 
-import java.io.BufferedReader;
-import java.io.DataInputStream;
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
-import java.io.FileWriter;
-import java.io.InputStreamReader;
+import java.io.*;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
 import java.util.Properties;
 
 /**
@@ -61,10 +59,10 @@
  *
  * </dl>
  *
- * @version v0.6, 2013/11/28 (November) -- Patch of Olivier Duplouy is added. Now you 
+ * @version v0.6, 2013/11/28 (November) -- Patch of Olivier Duplouy is added. Now you
  * can specify the representation type of your graph: dot, neato, fdp, sfdp, twopi, circo
  * @version v0.5.1, 2013/03/18 (March) -- Patch of Juan Hoyos (Mac support)
- * @version v0.5, 2012/04/24 (April) -- Patch of Abdur Rahman (OS detection + start subgraph + 
+ * @version v0.5, 2012/04/24 (April) -- Patch of Abdur Rahman (OS detection + start subgraph +
  * read config file)
  * @version v0.4, 2011/02/05 (February) -- Patch of Keheliya Gallaba is added. Now you
  * can specify the type of the output file: gif, dot, fig, pdf, ps, svg, png, etc.
@@ -107,7 +105,7 @@ public class GraphViz
 	/**
 	 * The image size in dpi. 96 dpi is normal size. Higher values are 10% higher each.
 	 * Lower values 10% lower each.
-	 * 
+	 *
 	 * dpi patch by Peter Mueller
 	 */
 	private int[] dpiSizes = {46, 51, 57, 63, 70, 78, 86, 96, 106, 116, 128, 141, 155, 170, 187, 206, 226, 249};
@@ -203,7 +201,7 @@ public void clearGraph(){
 	 */
 	public byte[] getGraph(String dot_source, String type, String representationType)
 	{
-		File dot;
+		Path dot = null;
 		byte[] img_stream = null;
 
 		try {
@@ -211,40 +209,33 @@ public byte[] getGraph(String dot_source, String type, String representationType
 			if (dot != null)
 			{
 				img_stream = get_img_stream(dot, type, representationType);
-				if (dot.delete() == false) 
-					System.err.println("Warning: " + dot.getAbsolutePath() + " could not be deleted!");
+				Files.delete(dot);
+
 				return img_stream;
 			}
 			return null;
-		} catch (java.io.IOException ioe) { return null; }
+		} catch (java.io.IOException ioe) {
+			System.err.println("Warning: " + dot.toString() + " could not be deleted!");
+			return null;
+		}
 	}
 
 	/**
 	 * Writes the graph's image in a file.
 	 * @param img   A byte array containing the image of the graph.
 	 * @param file  Name of the file to where we want to write.
-	 * @return Success: 1, Failure: -1
 	 */
-	public int writeGraphToFile(byte[] img, String file)
-	{
-		File to = new File(file);
-		return writeGraphToFile(img, to);
+	public void writeGraphToFile(byte[] img, String file) throws IOException {
+		writeGraphToFile(img, Paths.get(file));
 	}
 
 	/**
 	 * Writes the graph's image in a file.
 	 * @param img   A byte array containing the image of the graph.
 	 * @param to    A File object to where we want to write.
-	 * @return Success: 1, Failure: -1
 	 */
-	public int writeGraphToFile(byte[] img, File to)
-	{
-		try {
-			FileOutputStream fos = new FileOutputStream(to);
-			fos.write(img);
-			fos.close();
-		} catch (java.io.IOException ioe) { return -1; }
-		return 1;
+	public void writeGraphToFile(byte[] img, Path to) throws IOException {
+		Files.write(to, img, StandardOpenOption.CREATE);
 	}
 
 	/**
@@ -264,33 +255,34 @@ public int writeGraphToFile(byte[] img, File to)
 	 * @see http://www.graphviz.org under the Roadmap title
 	 * @return The image of the graph in .gif format.
 	 */
-	private byte[] get_img_stream(File dot, String type, String representationType)
+	private byte[] get_img_stream(Path dot, String type, String representationType)
 	{
-		File img;
+		Path img = null;
+		try {
+			img = Files.createTempFile(Paths.get(GraphViz.TEMP_DIR), "graph_", "."+type);
+		} catch (IOException e) {
+			System.err.println("Error:    in I/O processing of tempfile in dir " + GraphViz.TEMP_DIR+"\n");
+			e.printStackTrace();
+		}
 		byte[] img_stream = null;
 
-		try {
-			img = File.createTempFile("graph_", "."+type, new File(GraphViz.TEMP_DIR));
+		try  {
 			Runtime rt = Runtime.getRuntime();
 
 			// patch by Mike Chenault
 			// representation type with -K argument by Olivier Duplouy
-			String[] args = {DOT, "-T"+type, "-K"+representationType, "-Gdpi="+dpiSizes[this.currentDpiPos], dot.getAbsolutePath(), "-o", img.getAbsolutePath()};
+			String[] args = {DOT, "-T"+type, "-K"+representationType, "-Gdpi="+dpiSizes[this.currentDpiPos], dot.toString(), "-o", img.toString()};
 			Process p = rt.exec(args);
 			p.waitFor();
 
-			FileInputStream in = new FileInputStream(img.getAbsolutePath());
+			InputStream in = Files.newInputStream(img, StandardOpenOption.READ);
 			img_stream = new byte[in.available()];
 			in.read(img_stream);
-			// Close it if we need to
-			if( in != null ) in.close();
 
-			if (img.delete() == false) 
-				System.err.println("Warning: " + img.getAbsolutePath() + " could not be deleted!");
+			Files.delete(img);
 		}
 		catch (java.io.IOException ioe) {
-			System.err.println("Error:    in I/O processing of tempfile in dir " + GraphViz.TEMP_DIR+"\n");
-			System.err.println("       or in calling external command");
+			System.err.println("Error: in calling external command");
 			ioe.printStackTrace();
 		}
 		catch (java.lang.InterruptedException ie) {
@@ -307,20 +299,10 @@ private byte[] get_img_stream(File dot, String type, String representationType)
 	 * @param str Source of the graph (in dot language).
 	 * @return The file (as a File object) that contains the source of the graph.
 	 */
-	private File writeDotSourceToFile(String str) throws java.io.IOException
+	private Path writeDotSourceToFile(String str) throws IOException
 	{
-		File temp;
-		try {
-			temp = File.createTempFile("graph_", ".dot.tmp", new File(GraphViz.TEMP_DIR));
-			FileWriter fout = new FileWriter(temp);
-			fout.write(str);
-			fout.close();
-		}
-		catch (Exception e) {
-			System.err.println("Error: I/O error while writing the dot source to temp file!");
-			return null;
-		}
-		return temp;
+        Path path = Files.createTempFile(Paths.get(GraphViz.TEMP_DIR), "graph_", ".dot.tmp");
+		return Files.write(path, str.getBytes(), StandardOpenOption.CREATE);
 	}
 
 	/**
@@ -358,7 +340,7 @@ public String end_subgraph() {
 
 	/**
 	 * Read a DOT graph from a text file.
-	 * 
+	 *
 	 * @param input Input text file containing the DOT graph
 	 * source.
 	 */
@@ -366,18 +348,9 @@ public void readSource(String input)
 	{
 		StringBuilder sb = new StringBuilder();
 
-		try
-		{
-			FileInputStream fis = new FileInputStream(input);
-			DataInputStream dis = new DataInputStream(fis);
-			BufferedReader br = new BufferedReader(new InputStreamReader(dis));
-			String line;
-			while ((line = br.readLine()) != null) {
-				sb.append(line);
-			}
-			dis.close();
-		} 
-		catch (Exception e) {
+		try {
+			Files.lines(Paths.get(input)).forEach(sb::append);
+		} catch (IOException e) {
 			System.err.println("Error: " + e.getMessage());
 		}
 
diff --git a/src/com/github/jabbalaci/graphviz/Proba.java b/src/com/github/jabbalaci/graphviz/Proba.java
index fe9abdd..08e5093 100644
--- a/src/com/github/jabbalaci/graphviz/Proba.java
+++ b/src/com/github/jabbalaci/graphviz/Proba.java
@@ -1,6 +1,8 @@
 package com.github.jabbalaci.graphviz;
 
-import java.io.File;
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 
 public class Proba
 {
@@ -42,9 +44,13 @@ private void start()
 		// 		String repesentationType= "twopi";
 		// 		String repesentationType= "circo";
 		
-		File out = new File("/tmp/out"+gv.getImageDpi()+"."+ type);   // Linux
+		Path out = Paths.get("/tmp/out"+gv.getImageDpi()+"."+ type);   // Linux
 		//      File out = new File("c:/eclipse.ws/graphviz-java-api/out." + type);    // Windows
-		gv.writeGraphToFile( gv.getGraph(gv.getDotSource(), type, repesentationType), out );
+		try {
+			gv.writeGraphToFile( gv.getGraph(gv.getDotSource(), type, repesentationType), out );
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
 	}
 
 	/**
@@ -77,9 +83,13 @@ private void start2()
 		//		String repesentationType= "sfdp";
 		// 		String repesentationType= "twopi";
 		//		String repesentationType= "circo";
-		
-		File out = new File("/tmp/simple." + type);   // Linux
+
+		Path out = Paths.get("/tmp/simple." + type);   // Linux
 		//	   File out = new File("c:/eclipse.ws/graphviz-java-api/tmp/simple." + type);   // Windows
-		gv.writeGraphToFile( gv.getGraph(gv.getDotSource(), type, repesentationType), out );
+		try {
+			gv.writeGraphToFile( gv.getGraph(gv.getDotSource(), type, repesentationType), out );
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
 	}
 }