Added test class for FileSizer

src/test/java/org/pz/filededupe/FileSizerTest.java

@@ -0,0 +1,98 @@
+/*
+ * Project looks for duplicate files based on CRC-32 checksumming.
+ *
+ * Copyright (c) 2020 by Andrew Binstock. All rights reserved.
+ * Licensed under the Creative Commons Attribution, Share Alike license
+ * (CC BY-SA). Consult: https://creativecommons.org/licenses/by-sa/4.0/
+ */
+
+package org.pz.filededupe;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+
+import static org.junit.Assert.assertEquals;
+
+
+
+/**
+ * Test the routine that checks input files for their sizes
+ * @author alb
+ */
+public class FileSizerTest {
+
+    private File file1, file2, file3;
+
+    /* This folder and the files created in it will be deleted after
+     * tests are run, even in the event of failures or exceptions.
+     */
+    @Rule
+    public TemporaryFolder folder = new TemporaryFolder();
+
+    /* executed before every test */
+    @Before
+    public void setUp() {
+        try {
+            file1 = folder.newFile("testfile1.txt");
+            file2 = folder.newFile("testfile2.txt");
+            file3 = folder.newFile("testfile3.txt");
+        }
+        catch( IOException ioe ) {
+            System.err.println( "error creating temporary test file in " +
+                this.getClass().getSimpleName() );
+        }
+    }
+
+    /**
+     *  Write the same content to two files, and something different to a third file.
+     *  Then run all three through the FileSizer. The result should be a  filesize
+     *  table with two entries (since two files will have the same file size,
+     *  due to identical content, they'll be placed in one filesize entry).
+     */
+    @Test
+    public void test3FilesToBeChecksummed2ofWhichAreDupes() {
+
+        //write out data to the test files
+        try {
+
+            FileWriter fw1 = new FileWriter(file1.getAbsoluteFile());
+            BufferedWriter bw1 = new BufferedWriter(fw1);
+            bw1.write( "content for file1 and file2");
+            bw1.close();
+
+            FileWriter fw2 = new FileWriter(file2.getAbsoluteFile());
+            BufferedWriter bw2 = new BufferedWriter(fw2);
+            bw2.write( "content for file1 and file2");
+            bw2.close();
+
+            FileWriter fw3 = new FileWriter(file3.getAbsoluteFile());
+            BufferedWriter bw3 = new BufferedWriter(fw3);
+            bw3.write( "content for file3");
+            bw3.close();
+        }
+        catch( IOException ioe ) {
+            System.err.println( "Error creating temporary test files in " +
+                this.getClass().getSimpleName() );
+        }
+
+        LongStringListTable filesizeTable = new LongStringListTable();
+
+        FileSizer fsizer = new FileSizer();
+        fsizer.loadFileSizes(
+            folder.getRoot().getAbsolutePath(), true, filesizeTable );
+
+
+        // The table should contain two entries: that is, two file sizes--
+        // one file size will have two files attached to it, the other
+        // filesize will have only file3 attached to it.
+        assertEquals( 2, filesizeTable.getKeySet().size() );
+
+    }
+}