javase基础及所有文件day19-异常、io file day18作业答案

Day181Map的功能：(自己补齐)Vput(keykvaluev)VoidputAll(MapExtendsKextendsvm)添加一个集合,B:BooleancontainsKey(Objectkey) BooleancontainsValue(Objectvalue) Booleanequals(Objecto) C:Void VRemove(Objectkey) 查找指定的key，将该键值对移除Intget(Object Int packagepackage importjava.util.HashMap;importjava.util.I importjava.util.Map;publicclassTest_HashMappublicstaticvoidmain(String[]args)//TODOAuto-generatedmethod}publicstaticvoidexerciseStuHashMap()Map<Test_Student,String>stuMap=newHashMap<Test_Student,stuMap.put(newTest_Student(" ",48),"girl");stuMap.put(newTest_Student(" ",44),"girl");stuMap.put(newTest_Student(" ",35),"boy");stuMap.put(newTest_Student(" ",40),"girl");stuMap.put(newTest_Student(" ",35),"boy"); tor<Test_Student>it=stuMap.keySet().i tor();it.hasNext();){Test_Studentstu=it.next();Stringvalue=stuMap.get(stu);System.out.println(stu+">>>"+value);}}}package *Description*publicclassTest_StudentprivateStringprivateintpublicTest_Student(Stringname,intage)=name;this.age=age;}publicStringgetName()return}publicvoidsetName(Stringname)=}publicintgetAge()return}publicvoidsetAge(intage)this.age=}publicStringtoString()return"Test_Student[name="+name+",age="+age+} publicinthashCode()returnname.hashCode()+}publicbooleanequals(Objectobj)if(this==obj)returnif(!(objinstanceofTest_Student))returnTest_Studentstu=.equals(stu.getName())&&}}package;package;import importimportimportpublicclassTest1_TreeMapStringCountpublicstaticvoidmain(String[]args)//TODOAuto-generatedmethod}publicstaticvoidexerciseStringCount(){Stringstr="cbxzbvavdvgd";char[]chs=TreeMap<Character,Integer>strTreeMap=newTreeMap<Character,for(Characterc:chs)Integeri=if(i==null){strTreeMap.put(c,1);}elsestrTreeMap.put(c,}}StringBuildersb=newSet<Map.Entry<Character,Integer>>entrySet= tor<Map.Entry<Character,Integer>> tor();it.hasNext();)Map.Entry<Character,Integer>entry=it.next();Characterkey=entry.getKey();Integervalue=entry.getValue();}}}3、HashMapArrayList的使用。(特别掌握)预热班:01zhangsan；02就业班:01wangwu；02package importjava.util.HashMap;importjava.util.ArrayList;importjava.util.I importjava.util.Set;importjava.util.I importjava.util.List;publicclassTest2_HashMappublicstaticvoidmain(String[]args)}publicstaticvoidexerciseHashMap()HashMap<String,ArrayList<Test2_Student>>stuMap=newHashMap<String,ArrayList<Test2_Student>baseStuList=newArrayList<Test2_Student>();ArrayList<Test2_Student>advStuList=newArrayList<Test2_Student>();baseStuList.add(newTest2_Student("001"," baseStuList.add(newTest2_Student("002", advStuList.add(newTest2_Student("001"," advStuList.add(newTest2_Student("002", stuMap.put("base",baseStuList);stuMap.put("advance",advStuList);Set<String>keySet= tor<String>it=keySet.i tor();it.hasNext();){Stringkey=it.next();List<Test2_Student>stuValue= tor<Test2_Student>itValue=stuValue.i tor();itValue.hasNext();){Test2_Studentstu=itValue.next();System.out.println("\t"+}}}}package publicclassTest2_StudentprivateStringid,publicTest2_Student(Stringid,Stringname)this.id==}publicStringgetId()return}