实验二实验报告

第一部分

实验代码

public class MyUtil{
    public static String chengji(int grade){
        if ((grade < 0))
            return "错误";
        else if (grade < 60)
            return "不及格";
        else if (grade < 70)
            return "及格";
        else if (grade < 80)
            return "中等";
        else if (grade < 90)
            return "良好";
        else if (grade <= 100)
            return "优秀";
        else
            return "错误";
    }
}

测试代码

public class MyUtiltext {
    public static void main(String[] args) {
        zhengchang();
        yichang();
        bianjie();
    }
    public static void zhengchang(){
        if(MyUtil.chengji(55) != "不及格")
            System.out.println("test failed 1!");
        else if(MyUtil.chengji(65) != "及格")
            System.out.println("test failed 2!");
        else if(MyUtil.chengji(75) != "中等")
            System.out.println("test failed 3!");
        else if(MyUtil.chengji(85) != "良好")
            System.out.println("test failed 4!");
        else if(MyUtil.chengji(95) != "优秀")
            System.out.println("test failed 5!");
        else
            System.out.println("test passed!");
    }
    public  static void yichang(){
        if(MyUtil.chengji(-10) != "错误")
            System.out.println("test failed 6!");
        else if(MyUtil.chengji(115) != "错误")
            System.out.println("test failed 7!");
        else
            System.out.println("test passed!");
    }
    public  static void bianjie(){
        if(MyUtil.chengji(0) != "不及格")
            System.out.println("test failed 8!");
        else if(MyUtil.chengji(60) != "及格")
            System.out.println("test failed 9!");
        else if(MyUtil.chengji(70) != "中等")
            System.out.println("test failed 10!");
        else if(MyUtil.chengji(80) != "良好")
            System.out.println("test failed 11!");
        else if(MyUtil.chengji(90) != "优秀")
            System.out.println("test failed 12!");
        else if(MyUtil.chengji(100) != "优秀")
            System.out.println("test failed 13!");
        else
            System.out.println("test passed!");
    }
}

实验代码截图

第二部分

实验代码

import java.lang.StringBuffer;
public class StringBufferone {
        public static void main(String [] args){
            StringBuffer buffer = new StringBuffer();
            buffer.append('S');
            buffer.append("tringBuffer");
            System.out.println(buffer.charAt(1));
            System.out.println(buffer.capacity());
            System.out.println(buffer.indexOf("tring"));
            System.out.println("buffer = " + buffer.toString());
        }
}

测试代码

import junit.framework.TestCase;
import org.junit.Test;

public class StringBufferoneTest extends TestCase {
    StringBuffer a = new StringBuffer("StringBuffer");
    StringBuffer b = new StringBuffer("StringBufferStringBuffer");
    StringBuffer c = new StringBuffer("StringBufferStringBufferStringBuffer");
    @Test
    public void testcharAt() throws Exception{
        assertEquals('S',a.charAt(0));
        assertEquals('g',b.charAt(5));
        assertEquals('S',c.charAt(12));
    }
    public void  testcapacity() throws Exception{
        assertEquals(28,a.capacity());
        assertEquals(40,b.capacity());
        assertEquals(52,c.capacity());
    }
    public void testindexOf() throws Exception{
        assertEquals(a.indexOf("Str"),0);
        assertEquals(6,b.indexOf("Buf"));
        assertEquals(9,c.indexOf("fer"));
    }
}

程序运行结果

第三部分

实验代码

abstract class Data {
    abstract public void DisplayValue();
}
class Integer extends  Data {
    int value;
    Integer() {
        value=100;
    }
    public void DisplayValue(){
        System.out.println (value);
    }
}
class Short extends  Data {
    short value;
    Short() {
        value=100;
    }
    public void DisplayValue(){
        System.out.println (value);
    }
}
abstract class Factory {
    abstract public Data CreateDataObject();
}
class   IntFactory extends Factory {
    public Data CreateDataObject(){
        return new Integer();
    }
}
class ShortFactory extends Factory {
    public Data CreateDataObject(){
        return new Integer();
    }
}
class Document {
    Data pd;
    Document(Factory pf){
        pd = pf.CreateDataObject();
    }
    public void DisplayData(){
        pd.DisplayValue();
    }
}
public class MyDoc {
    static Document d;
    static Document c;
    public static void main(String[] args) {
        d = new Document(new IntFactory());
        c = new Document(new ShortFactory());
        d.DisplayData();
        c.DisplayData();
    }
}

运行结果

第四部分

实验代码

public class Complex {
    int RealPart;
    int ImagePart;
    public Complex(){}
    public Complex(int R,int I){
        RealPart = R;
        ImagePart = I;
    }
    public int getRealPart(){
        return RealPart;
    }
    public int getImagePart(){
        return ImagePart;
    }
    public String toString(){
        String s = new String();
        if(ImagePart>0)
            s = getRealPart()+"+"+getImagePart()+"i";
        if(ImagePart==0)
            s = getRealPart()+"";
        if(ImagePart<0)
            s = getRealPart()+""+getImagePart()+"i";
        if(RealPart==0)
            s = getImagePart()+"i";
        if(ImagePart==0&&RealPart==0)
            s = "0";
        return s;
    }
    public Complex ComplexAdd(Complex a){
        Complex d = new Complex();
        d.RealPart = RealPart + a.RealPart;
        d.ImagePart = ImagePart + a.ImagePart;
        return d;
    }
    public Complex ComplexSub(Complex a){
        Complex d = new Complex();
        d.RealPart = RealPart - a.RealPart;
        d.ImagePart = ImagePart - a.ImagePart;
        return d;
    }
    public Complex ComplexMulti(Complex a){
        Complex d = new Complex();
        d.RealPart = RealPart*a.RealPart - ImagePart*a.ImagePart;
        d.ImagePart = RealPart*a.ImagePart + ImagePart*a.RealPart;
        return d;
    }
    public Complex ComplexDiv(Complex a) {
        Complex d = new Complex();
        d.RealPart = (RealPart * a.RealPart + ImagePart * a.ImagePart) / (a.RealPart * a.RealPart + a.ImagePart * a.ImagePart);
        d.ImagePart = (ImagePart * a.RealPart - RealPart * a.ImagePart) / (a.RealPart * a.RealPart + a.ImagePart * a.ImagePart);
        return d;
    }
}

测试代码

import junit.framework.TestCase;
import org.junit.Test;

public class ComplexTest extends TestCase {
    Complex a = new Complex(1,2);
    Complex b = new Complex(-1,-2);
    Complex c = new Complex(0,0);
    @Test
    public void testGetRealPart() {
        assertEquals(1,a.getRealPart());
        assertEquals(-1,b.getRealPart());
        assertEquals(0,c.getRealPart());
    }
    @Test
    public void testGetImagePart() {
        assertEquals(2,a.getImagePart());
        assertEquals(-2,b.getImagePart());
        assertEquals(0,c.getImagePart());
    }
    @Test
    public void testToString() {
        assertEquals("1+2i",a.toString());
        assertEquals("-1-2i",b.toString());
        assertEquals("0",c.toString());
    }
    @Test
    public void testComplexAdd() {
        String q = a.ComplexAdd(b).toString();
        String w = b.ComplexAdd(c).toString();
        String e = c.ComplexAdd(a).toString();
        assertEquals("0",q);
        assertEquals("-1-2i",w);
        assertEquals("1+2i",e);
    }
    @Test
    public void testComplexSub() {
        String r = a.ComplexSub(b).toString();
        String t = b.ComplexSub(c).toString();
        String y = c.ComplexSub(a).toString();
        assertEquals("2+4i",r);
        assertEquals("-1-2i",t);
        assertEquals("-1-2i",y);
    }
    @Test
    public void testComplexMulti() {
        String u = a.ComplexMulti(b).toString();
        String i = b.ComplexMulti(c).toString();
        String o = c.ComplexMulti(a).toString();
        assertEquals("3-4i",u);
        assertEquals("0",i);
        assertEquals("0",o);
    }
    @Test
    public void testComplexDiv() {
        String r = a.ComplexDiv(b).toString();
        String y = c.ComplexDiv(a).toString();
        assertEquals("-1",r);
        assertEquals("0",y);
    }
}

实验结果

第五部分

实验结果