Assert File

FileTestOperations.java

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;

import junitx.framework.AssertionFailedError;

import org.junit.Assert;

public class FileTestOperations {

	static boolean fail = false;
	
	public static void assertFileWithTemplate(final String file, final String template) {
		assertFileWithTemplate(new File(file), new File(template));
	}
	
	public static void assertFileWithTemplate(final File file, final File template) {
		fail = false;
		
        Assert.assertNotNull(template);
        Assert.assertNotNull(file);

        Assert.assertTrue("File does not exist [" + template.getAbsolutePath() + "]", template.exists());
        Assert.assertTrue("File does not exist [" + file.getAbsolutePath() + "]", file.exists());

        Assert.assertTrue("Template file not readable", template.canRead());
        Assert.assertTrue("Actual file not readable", file.canRead());

        FileInputStream templateStream = null;
        FileInputStream fileStream = null;
        
        try {
            try {
                templateStream = new FileInputStream(template);
                fileStream = new FileInputStream(file);
    
                BufferedReader fileData = new BufferedReader(new InputStreamReader(fileStream));
                BufferedReader templData = new BufferedReader(new InputStreamReader(templateStream));
    
                assertLines(fileData, templData);
            } finally {
            	templateStream.close();
            	fileStream.close();
            }
        } catch (IOException e) {
            throw new AssertionFailedError(e);
        }

        if (fail) {
        	Assert.fail("Generated file is not equal provided template.");
        }
	}
	
	private static void assertLines(final BufferedReader fileData, final BufferedReader templData) throws IOException {
		String fileLine;
		String templateLine;
		
		for (int lineNumber = 1; true; lineNumber++) {
			fileLine = fileData.readLine();
			templateLine = templData.readLine();
						
			if (fileLine == null && templateLine == null) {
				return;
			}
			
			verifyFileLengh(fileLine, templateLine, lineNumber);
			
			if (!templateLine.equals(fileLine)) {
				searchCaracterWithDiference(fileLine.toCharArray(), templateLine.toCharArray(), lineNumber);
			}
		}
	}
	
	private static void searchCaracterWithDiference(char[] lineChars, char[] templChars, int lineNumber) {
		int column;
		for (int i = 0; i < templChars.length; i++) {
			if (lineChars[i] != templChars[i]) {
				column = i + 1;
				System.out.println("Difference was found at line " + lineNumber + ", near column " + column + ". \"" + String.valueOf(lineChars[i]) + "\" expected, \"" + String.valueOf(templChars[i] + "\" received."));
				fail = true;
			}
		}
	}

	private static void verifyFileLengh(final String fileLine, final String templateLine, final int line) {
		Assert.assertFalse("Generated file has less lines than template.", fileLine == null && templateLine != null);
		Assert.assertFalse("Generated file has more lines than template", fileLine != null && templateLine == null);
		Assert.assertFalse("Line " + line + " from the generated file is larger than template.", fileLine.length() > templateLine.length());
		Assert.assertFalse("Line " + line + " from generated file is smaller than template.", fileLine.length() < templateLine.length());
	}
}

@Test
public void testAssertFileExample() throws IOException {
    FileTestOperations.assertFileWithTemplate(new File("/home/cristianobaldin/arq1.txt"), new File("/home/cristianobaldin/arq2.txt"));
}