Example usage for java.io FileInputStream read

Introduction

In this page you can find the example usage for java.io FileInputStream read.

Prototype

public int read(byte b[]) throws IOException 

Source Link

Document

Reads up to b.length bytes of data from this input stream into an array of bytes.

Usage

From source file:eu.europa.esig.dss.applet.util.FileTypeDetectorUtils.java

/**
 * @param file//  w  ww. j  a  va  2  s .  co m
 * @return
 * @throws IOException
 */
private static String extractPreambleString(final File file) throws IOException {

    FileInputStream inputStream = null;

    try {
        inputStream = new FileInputStream(file);

        final byte[] preamble = new byte[5];
        final int read = inputStream.read(preamble);
        if (read < 5) {
            throw new RuntimeException();
        }

        return new String(preamble);
    } finally {
        IOUtils.closeQuietly(inputStream);
    }
}

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From source file:Main.java

public static byte[] getBytesFromFile(File f) {

    if (f == null) {
        return null;
    }/*  ww w. j  av a 2s .co m*/

    FileInputStream stream = null;
    ByteArrayOutputStream out = null;

    try {
        stream = new FileInputStream(f);
        out = new ByteArrayOutputStream(1024);
        byte[] b = new byte[1024];
        int n;
        while ((n = stream.read(b)) != -1)
            out.write(b, 0, n);

    } catch (Exception e) {
    }

    try {
        if (out != null)
            out.close();

        if (stream != null)
            stream.close();
    } catch (Exception e) {
    }

    System.gc();

    if (out == null)
        return null;

    return out.toByteArray();
}

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From source file:Main.java

/**
 * Dump the database file to external storage
 *
 * @param packageName/*from www  .  j  a v  a 2 s  . c o  m*/
 * @param fileName
 * @throws IOException
 */
public static void dumpDatabase(String packageName, String fileName) throws IOException {
    File dbFile = new File("/data/data/" + packageName + "/databases/" + fileName);
    if (dbFile.exists()) {
        FileInputStream fis = new FileInputStream(dbFile);
        String outFileName = Environment.getExternalStorageDirectory() + "/" + fileName;
        OutputStream output = new FileOutputStream(outFileName);
        byte[] buffer = new byte[1024];
        int length;
        while ((length = fis.read(buffer)) > 0) {
            output.write(buffer, 0, length);
        }
        output.flush();
        output.close();
        fis.close();
    }
}

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From source file:Main.java

public static boolean fileCopy(String from, String to) {
    boolean result = false;

    int size = 1 * 1024;

    FileInputStream in = null;
    FileOutputStream out = null;//from   w  w w  . j a  va  2 s. c om
    try {
        in = new FileInputStream(from);
        out = new FileOutputStream(to);
        byte[] buffer = new byte[size];
        int bytesRead = -1;
        while ((bytesRead = in.read(buffer)) != -1) {
            out.write(buffer, 0, bytesRead);
        }
        out.flush();
        result = true;
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            if (in != null) {
                in.close();
            }
        } catch (IOException e) {
        }
        try {
            if (out != null) {
                out.close();
            }
        } catch (IOException e) {
        }
    }
    return result;
}

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From source file:com.net.plus.common.Utils.Util.java

public static byte[] getBytesFromFile(String file) {
    if (file == null) {
        return null;
    }/*from  w  ww .j  a  v a2s  .com*/
    byte[] ret = null;
    FileInputStream in = null;
    try {
        in = new FileInputStream(file);
        ByteArrayOutputStream out = new ByteArrayOutputStream(4096);
        byte[] b = new byte[4096];
        int n;
        while ((n = in.read(b)) != -1) {
            out.write(b, 0, n);
        }
        ret = out.toByteArray();
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        if (in != null) {
            try {
                in.close();
            } catch (IOException e) {

            }
        }
    }
    return ret;
}

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From source file:Compress.java

/** Zip the contents of the directory, and save it in the zipfile */
public static void zipDirectory(String dir, String zipfile) throws IOException, IllegalArgumentException {
    // Check that the directory is a directory, and get its contents
    File d = new File(dir);
    if (!d.isDirectory())
        throw new IllegalArgumentException("Compress: not a directory:  " + dir);
    String[] entries = d.list();// ww w  . ja  v a2 s .  c o m
    byte[] buffer = new byte[4096]; // Create a buffer for copying
    int bytes_read;

    // Create a stream to compress data and write it to the zipfile
    ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipfile));

    // Loop through all entries in the directory
    for (int i = 0; i < entries.length; i++) {
        File f = new File(d, entries[i]);
        if (f.isDirectory())
            continue; // Don't zip sub-directories
        FileInputStream in = new FileInputStream(f); // Stream to read file
        ZipEntry entry = new ZipEntry(f.getPath()); // Make a ZipEntry
        out.putNextEntry(entry); // Store entry
        while ((bytes_read = in.read(buffer)) != -1)
            // Copy bytes
            out.write(buffer, 0, bytes_read);
        in.close(); // Close input stream
    }
    // When we're done with the whole loop, close the output stream
    out.close();
}

---

From source file:FileCopy.java

public static void copy(String fromFileName, String toFileName) throws IOException {
    File fromFile = new File(fromFileName);
    File toFile = new File(toFileName);

    if (!fromFile.exists())
        throw new IOException("FileCopy: " + "no such source file: " + fromFileName);
    if (!fromFile.isFile())
        throw new IOException("FileCopy: " + "can't copy directory: " + fromFileName);
    if (!fromFile.canRead())
        throw new IOException("FileCopy: " + "source file is unreadable: " + fromFileName);

    if (toFile.isDirectory())
        toFile = new File(toFile, fromFile.getName());

    if (toFile.exists()) {
        if (!toFile.canWrite())
            throw new IOException("FileCopy: " + "destination file is unwriteable: " + toFileName);
        System.out.print("Overwrite existing file " + toFile.getName() + "? (Y/N): ");
        System.out.flush();/*from   w w w.jav a  2  s .co m*/
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        String response = in.readLine();
        if (!response.equals("Y") && !response.equals("y"))
            throw new IOException("FileCopy: " + "existing file was not overwritten.");
    } else {
        String parent = toFile.getParent();
        if (parent == null)
            parent = System.getProperty("user.dir");
        File dir = new File(parent);
        if (!dir.exists())
            throw new IOException("FileCopy: " + "destination directory doesn't exist: " + parent);
        if (dir.isFile())
            throw new IOException("FileCopy: " + "destination is not a directory: " + parent);
        if (!dir.canWrite())
            throw new IOException("FileCopy: " + "destination directory is unwriteable: " + parent);
    }

    FileInputStream from = null;
    FileOutputStream to = null;
    try {
        from = new FileInputStream(fromFile);
        to = new FileOutputStream(toFile);
        byte[] buffer = new byte[4096];
        int bytesRead;

        while ((bytesRead = from.read(buffer)) != -1)
            to.write(buffer, 0, bytesRead); // write
    } finally {
        if (from != null)
            try {
                from.close();
            } catch (IOException e) {
                ;
            }
        if (to != null)
            try {
                to.close();
            } catch (IOException e) {
                ;
            }
    }
}

---

From source file:cc.arduino.utils.FileHash.java

/**
 * Calculate a message digest of a file using the algorithm specified. The
 * result is a string containing the algorithm name followed by ":" and by the
 * resulting hash in hex.//w  w w .  j  a  va 2  s.  c  om
 *
 * @param file
 * @param algorithm For example "SHA-256"
 * @return The algorithm followed by ":" and the hash, for example:<br />
 * "SHA-256:ee6796513086080cca078cbb383f543c5e508b647a71c9d6f39b7bca41071883"
 * @throws IOException
 * @throws NoSuchAlgorithmException
 */
public static String hash(File file, String algorithm) throws IOException, NoSuchAlgorithmException {
    FileInputStream in = null;
    try {
        in = new FileInputStream(file);
        byte buff[] = new byte[10240];
        MessageDigest digest = MessageDigest.getInstance(algorithm);
        while (in.available() > 0) {
            int read = in.read(buff);
            digest.update(buff, 0, read);
        }
        byte[] hash = digest.digest();
        String res = "";
        for (byte b : hash) {
            int c = b & 0xFF;
            if (c < 0x10)
                res += "0";
            res += Integer.toHexString(c);
        }
        return algorithm + ":" + res;
    } finally {
        IOUtils.closeQuietly(in);
    }
}

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From source file:Main.java

public static boolean copyFile(File src, File dest) {
    if (!src.exists())
        return false;

    FileInputStream fis = null;
    FileOutputStream fos = null;/*  w w  w . j av a  2s  . c  o m*/
    try {
        fis = new FileInputStream(src);
        fos = new FileOutputStream(dest);

        byte[] buffer = new byte[2048];
        int bytesread = 0;
        while ((bytesread = fis.read(buffer)) != -1) {
            if (bytesread > 0)
                fos.write(buffer, 0, bytesread);
        }

        return true;

    } catch (FileNotFoundException e) {
        return false;
    } catch (IOException e) {
        return false;
    } finally {
        if (fis != null) {
            try {
                fis.close();
            } catch (Exception e2) {
            }
        }

        if (fos != null) {
            try {
                fos.close();
            } catch (Exception e2) {
            }
        }
    }
}

---

From source file:Main.java

public static String checksum(String path, String algorithm) {
    MessageDigest md = null;/* www .j av a 2s .  co m*/

    try {
        md = MessageDigest.getInstance(algorithm);
    } catch (NoSuchAlgorithmException e) {
        throw new RuntimeException(e);
    }

    FileInputStream i = null;

    try {
        i = new FileInputStream(path);
    } catch (FileNotFoundException e) {
        throw new RuntimeException(e);
    }

    byte[] buf = new byte[1024];
    int len = 0;

    try {
        while ((len = i.read(buf)) != -1) {
            md.update(buf, 0, len);
        }
    } catch (IOException e) {

    }

    byte[] digest = md.digest();

    // HEX
    StringBuilder sb = new StringBuilder();
    for (byte b : digest) {
        sb.append(Integer.toString((b & 0xff) + 0x100, 16).substring(1));
    }

    return sb.toString();

}

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