Java 源代码测试：使用 Eclipse 编译并执行 Printtokens2.java

使用 Eclipse 建立项目并执行 Printtokens2.java 测试

1. 项目建立和执行

1. **打开 Eclipse 并创建一个新项目。**选择 File -> New -> Java Project，输入项目名称，例如“Printtokens2Test”。2. **导入 Printtokens2.java 代码。**将代码复制到项目中的 src 目录下。3. **编写 JUnit 测试代码。**在项目中创建测试类，例如 TestPrinttokens2.java，并在其中添加测试用例。4. **执行测试。**右键点击测试类，选择 Run As -> JUnit Test。

2. 白盒测试用例设计

需满足判定+条件覆盖准则，具体设计如下：

| 输入 | 期望输出 ||----------------------|---------------------------------------------|| null | 返回 null || '' | 返回 null || 'and or if' | keyword, 'and'. keyword, 'or'. keyword, 'if'. || '[]() , /' |lsquare. rsquare. lparen. rparen. comma. bquote. divide.||'test1 test2' |identifier, 'test1'. identifier, 'test2'.||'#a' |character, 'a'. ||'123 456' |numeric, 123. numeric, 456. ||'string'`` | string, 'string'. || ; | semicolon. || 'abc;123' | identifier, 'abc'. semicolon. numeric, 123. || 'not_exist_file.txt' | 返回 null |

3. 测试用例具体输入和预期输出

| 输入 | 期望输出 ||----------------------|---------------------------------------------|| null | null || '' | null || 'and or if' | keyword, 'and'. keyword, 'or'. keyword, 'if'. || '[]() , /' |lsquare. rsquare. lparen. rparen. comma. bquote. divide.||'test1 test2' |identifier, 'test1'. identifier, 'test2'.||'#a' |character, 'a'. ||'123 456' |numeric, 123. numeric, 456. ||'string'`` | string, 'string'. || ; | semicolon. || 'abc;123' | identifier, 'abc'. semicolon. numeric, 123. || 'not_exist_file.txt' | null |

4. JUnit 测试代码javapackage JUnit4Printtokens2;

import static org.junit.Assert.assertEquals;import org.junit.Test;import java.io.BufferedReader;import java.io.IOException;import java.io.StringReader;

public class TestPrinttokens2 {

@Test	public void testOpenTokenStreamNull() throws IOException {		Printtokens2 t = new Printtokens2();		BufferedReader br = t.open_token_stream(null);		assertEquals(null, br);	}

@Test	public void testOpenTokenStreamEmptyString() throws IOException {		Printtokens2 t = new Printtokens2();		BufferedReader br = t.open_token_stream('');		assertEquals(null, br);	}

@Test	public void testGetToken() throws IOException {		Printtokens2 t = new Printtokens2();		BufferedReader br = new BufferedReader(new StringReader('and or if'));		String tok = t.get_token(br);		assertEquals('and', tok);		tok = t.get_token(br);		assertEquals('or', tok);		tok = t.get_token(br);		assertEquals('if', tok);	}

@Test	public void testPrintTokenKeyword() {		Printtokens2 t = new Printtokens2();		t.print_token('and');		assertEquals('keyword,'and'.

', systemOut()); }

@Test	public void testPrintTokenSpecSymbol() {		Printtokens2 t = new Printtokens2();		t.print_token('(');		assertEquals('lparen.

', systemOut()); }

@Test	public void testPrintTokenIdentifier() {		Printtokens2 t = new Printtokens2();		t.print_token('test1');		assertEquals('identifier,'test1'.

', systemOut()); }

@Test	public void testPrintTokenNumConstant() {		Printtokens2 t = new Printtokens2();		t.print_token('123');		assertEquals('numeric,123.

', systemOut()); }

@Test	public void testPrintTokenCharConstant() {		Printtokens2 t = new Printtokens2();		t.print_token('#a');		assertEquals('character,'a'.

', systemOut()); }

@Test	public void testPrintTokenStrConstant() {		Printtokens2 t = new Printtokens2();		t.print_token('string');		assertEquals('string,'string'.

', systemOut()); }

@Test	public void testPrintTokenSemicolon() {		Printtokens2 t = new Printtokens2();		t.print_token(';');		assertEquals('semicolon.

', systemOut()); }

// ... 其他测试用例

private String systemOut() {		// ... 获取 System.out 内容