JUNIT 테스트 작성 방법

package com.jini.ch4;

import java.io.*;
import junit.framework.*;


public class FileReaderTester extends TestCase {
 
 private FileReader _input;
 private FileReader _empty;
 private static final String FILE_NAME = "c:/Users/jini/Desktop/data.txt";
 
 public static void main (String[] args) {
  //1. 기본적인 Test 실행 방식.
  junit.textui.TestRunner.run(suite());
  
  //2. 해당 클래스에서 test로 시작하는 모든 메소드를 테스트 하도록 함.
  junit.textui.TestRunner.run(new TestSuite(FileReaderTester.class));
  
  //3. 여러 클래스의 Test Suite를 연결하기 위한 MasterTester 클래스 방식/
  junit.textui.TestRunner.run( suite2());
 }

 public FileReaderTester(String name) {
  super(name);
 }
 
 /**
  * 메소드명을 파라미터로 하는 TestSuite 
  * @throws IOException
  */
 public static Test suite() {
  TestSuite suite = new TestSuite();
  suite.addTest(new FileReaderTester("testRead"));
  suite.addTest(new FileReaderTester("testReadAtEnd"));
  return suite;
 }
 
 public static Test suite2() {
  TestSuite result = new TestSuite();
  result.addTest(new TestSuite(FileReaderTester.class));
  result.addTest(new TestSuite(FileReaderTester.class));
  return result;
 }
 
 public void testRead() throws IOException {
  char ch = '&';
  for(int x = 0; x < 4; x++) {
   ch = (char)_input.read();
  }
  
  assertEquals('d', ch);
 }
 
 public void testReadAtEnd() throws IOException {
  int ch = -1234;
  for(int x = 0; x < 141; x++) {
   ch = _input.read();
  }
  
  assertEquals("read at end", -1, _input.read());
 }
 
 public void testReadBoundaries() throws IOException {
  assertEquals("read first char", 'B', _input.read());
  int ch;
  for(int x = 0; x < 140; x++) {
   ch = _input.read();
  }
  
  assertEquals("read last char", '6', _input.read());
  assertEquals("read at end", -1, _input.read());
  assertEquals("read past end", -1, _input.read());
 }
 
 public void testEmptyRead() throws IOException {
  assertEquals(-1, _empty.read());
 }
 
 public void testReadAfterClose() throws Exception {
  _input.close();
  
  try {
   _input.read();
   fail("read past end에 예외가 발생하지 않음");
  } catch (IOException e) {
   e.printStackTrace();
  }
 }
 
 protected void setUp() {
  try {
   _input = new FileReader(FILE_NAME);
   _empty = newEmptyFile();
  } catch (IOException e) {
   throw new RuntimeException(e.toString());
  }
 }
 
 protected void tearDown() {
  try {
   _input.close();
  } catch (IOException e) {
   throw new RuntimeException("테스트 파일을 닫는 중 에러 발생");
  }
 }
 
 private FileReader newEmptyFile() throws IOException {
  File empty = new File(FILE_NAME);
  FileOutputStream out = new FileOutputStream(empty);
  out.close();
  return new FileReader(empty);
 }
}