Rename classes and methods to fit camelCase

1 files changed, 172 insertions, 0 deletions

diff --git a/src/main/java/org/openslx/imagemaster/crcchecker/CrcFile.java b/src/main/java/org/openslx/imagemaster/crcchecker/CrcFile.java
new file mode 100644
index 0000000..542234b
--- /dev/null
+++ b/src/main/java/org/openslx/imagemaster/crcchecker/CrcFile.java
@@ -0,0 +1,172 @@
+package org.openslx.imagemaster.crcchecker;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.zip.CRC32;
+
+/**
+ * Represents a crc file
+ */
+public class CrcFile
+{
+	private File file = null;
+	private List<Integer> crcSums = null;
+	private Boolean valid = null;
+
+	/**
+	 * Loads a crcFile from file
+	 * 
+	 * @param filename
+	 */
+	public CrcFile( String filename )
+	{
+		this.file = new File( filename );
+	}
+
+	/**
+	 * Creates a crc file which is not on the drive.
+	 * 
+	 * @param crcSums
+	 */
+	public CrcFile( List<Integer> crcSums )
+	{
+		this.crcSums = crcSums;
+	}
+
+	/**
+	 * Creates a new crc file with the given sums.
+	 * The first crc sum in the list needs to be the sum over the other sums.
+	 * Deletes existing files with the same name.
+	 * 
+	 * @param listOfCrcSums The list of the crc sums that are going into the crc file
+	 * @param filename Where to save the created crc file
+	 * @throws IOException If it's not possible to write the file
+	 */
+	public static CrcFile writeCrcFile( List<Integer> listOfCrcSums, String filename ) throws IOException
+	{
+		File file = new File( filename );
+		
+		if ( file.exists() )
+			file.delete();
+		
+		FileOutputStream fos = new FileOutputStream( file );
+		DataOutputStream dos = new DataOutputStream( fos );
+
+		for ( Integer sum : listOfCrcSums ) {
+			dos.writeInt( sum.intValue() );
+		}
+
+		dos.close();
+		return new CrcFile( filename );
+	}
+
+	/**
+	 * Checks if given sums are valid.
+	 * 
+	 * @param listOfCrcSums
+	 * @return
+	 */
+	public static boolean sumsAreValid( List<Integer> listOfCrcSums )
+	{
+		if ( listOfCrcSums == null || listOfCrcSums.isEmpty() )
+			return false;
+
+		int masterSum = listOfCrcSums.get( 0 );		// don't use the first sum for the calculation because it is the sum over the other sums
+		int size = listOfCrcSums.size();
+
+		CRC32 crcCalc = new CRC32();
+
+		for ( int i = 1; i < size; i++ ) {
+			crcCalc.update( ByteBuffer.allocate( 4 ).putInt( listOfCrcSums.get( i ) ).array() ); // update the crc calculator with the next 4 bytes of the integer
+		}
+
+		return ( masterSum == Integer.reverseBytes( (int)crcCalc.getValue() ) );
+	}
+
+	/**
+	 * Checks if this crc file is valid.
+	 * (If the crc over the file is equal to the first crc sum.)
+	 * 
+	 * @return Whether the crc file is valid
+	 * @throws IOException If the file could not be read or could not be found
+	 */
+	public boolean isValid() throws IOException
+	{
+		if ( valid == null ) {
+			if ( file == null ) {
+				valid = sumsAreValid( this.crcSums );
+			} else {
+				if ( crcSums == null )
+					loadSums();
+				valid = sumsAreValid( this.crcSums );
+			}
+		}
+		return valid;
+	}
+
+	/**
+	 * Get a specified crcSum for a block number
+	 * 
+	 * @param blockNumber
+	 * @return The crcSum or 0 if the block number is invalid
+	 * @throws IOException If the crcSums could not be loaded from file
+	 */
+	public int getCRCSum( int blockNumber ) throws IOException
+	{
+		if ( crcSums == null )
+			loadSums();
+		if ( crcSums.size() == 0 )
+			return 0;
+
+		if ( blockNumber < 0 )
+			return 0;
+		if ( blockNumber > crcSums.size() - 2 )
+			return 0;
+
+		return crcSums.get( blockNumber + 1 );
+	}
+
+	/**
+	 * Returns the loaded crcSums.
+	 * 
+	 * @return The loaded crcSums
+	 * @throws IOException If the crcSums could not be loaded from file
+	 */
+	public List<Integer> getCrcSums() throws IOException
+	{
+		if ( crcSums == null )
+			loadSums();
+		if ( crcSums.size() == 0 )
+			return new ArrayList<>();
+		return this.crcSums;
+	}
+
+	private void loadSums() throws IOException
+	{
+		if ( crcSums != null )
+			return;
+		// the crcSums were not read yet
+		DataInputStream dis = new DataInputStream( new FileInputStream( file ) );
+		crcSums = new ArrayList<>();
+		for ( int i = 0; i < file.length() / 4; i++ ) {
+			crcSums.add( dis.readInt() );
+		}
+		dis.close();
+	}
+
+	public int getMasterSum() throws IOException
+	{
+		if ( crcSums == null )
+			loadSums();
+		if ( crcSums.size() == 0 )
+			return 0;
+		return this.crcSums.get( 0 );
+	}
+}