java按照首字母排序

1. java 汉字首字母排序

我知道用java可以通过汉字的获得到首字母。下面是源码：
import net.sourceforge.pinyin4j.PinyinHelper;

public class PinyinAPI {

/**
* 提取每个汉字的首字母(大写)
*
* @param str
* @return
*/
public static String getPinYinHeadChar(String str) {
if (isNull(str)) {
return "";
}
String convert = "";
for (int j = 0; j < str.length(); j++) {
char word = str.charAt(j);
// 提取汉字的首字母
String[] pinyinArray = PinyinHelper.toHanyuPinyinStringArray(word);
if (pinyinArray != null) {
convert += pinyinArray[0].charAt(0);
}
else {
convert += word;
}
}

convert = string2AllTrim(convert);
return convert.toUpperCase();
}

/*
* 判断字符串是否为空
*/

public static boolean isNull(Object strData) {
if (strData == null || String.valueOf(strData).trim().equals("")) {
return true;
}
return false;
}

/**
* 去掉字符串包含的所有空格
*
* @param value
* @return
*/
public static String string2AllTrim(String value) {
if (isNull(value)) {
return "";
}
return value.trim().replace(" ", "");
}

public static void main(String[] args) {
String ss = PinyinAPI.getPinYinHeadChar("中国");
System.out.print(ss);//ZG
}
}

2. JAVA编写程序，对英文单词按照字母顺序进行排序（升序or降序）

Easy!

import java.util.ArrayList;
import java.util.Collections;

public class Main {

/**
* @param args
* the command line arguments
*/
public static void main(String[] args) {
String target = "John Bill Peter ";

ArrayList<String> list = new ArrayList<String>();
for (String temp : target.split(" ")) {
list.add(temp);
}

Collections.sort(list);

for(int i = list.size(); i > 0; i--){
System.out.println(list.get(i-1) + " ");
}

}

}

----------------
Peter
John
Bill

3. java 中有城市类 存在arraylist 怎么让它按名字首字母排序

参考代码如下

importjava.util.ArrayList;
importjava.util.Comparator;

publicclassListDemo{
	publicstaticvoidmain(String[]args){
		ArrayList<String>city=newArrayList<String>();
		city.add("Jonesboro");
		city.add("Chaohu");
		city.add("LittleRock");
		city.add("bridgeport");
		city.add("Rome");
		city.add("chicago");
		System.out.println("排序前"+city);
		//排序.
		city.sort(newComparator<String>(){
			//重点是这个函数
			publicintcompare(Stringo1,Stringo2){
				//忽略掉大小写后,进行字符串的比较
				Strings1=o1.toLowerCase();
				Strings2=o2.toLowerCase();
				returns1.compareTo(s2);//从a-z的排
				//returns2.compareTo(s1);//从z-a的排
			}
		});
		System.out.println("排序后"+city);
	}
}

运行效果

排序前[Jonesboro,Chaohu,LittleRock,bridgeport,Rome,chicago]
排序后[bridgeport,Chaohu,chicago,Jonesboro,LittleRock,Rome]

4. Java中让用户随机输入一串名字并按照字母顺序输出

importjava.util.Scanner;

publicclassTest{
	publicstaticvoidmain(String[]args){
		=newScanner(System.in);
		System.out.println("输入一组名字:");
		Strings=sc.nextLine();
		String[]strs=s.split("");
		Stringtemp="";
		for(inti=0;i<strs.length;i++){
			for(intj=i;j>0;j--){
				if(strs[j].charAt(0)<strs[j-1].charAt(0)){
					temp=strs[j-1];
					strs[j-1]=strs[j];
					strs[j]=temp;
				}else
					break;
			}
		}
		for(inti=0;i<strs.length;i++){
			System.out.print(strs[i]+"");
		}
	}
}

5. JAVA通过数组按首字母排序

package demo;

import java.util.Arrays;

public class Test {

public void sortStringArray() {
String[] arrayToSort = new String[] { "Oscar", "Charlie", "Ryan",
"Adam", "David","aff","Aff" };
System.out.println();
System.out.println("字符型数组排序,排序前:");
for (int i = 0; i < arrayToSort.length; i++){
System.out.print(arrayToSort[i]+",");
}
System.out.println();
System.out.println("排序后:");
// 调用数组的静态排序方法sort,且不区分大小写
Arrays.sort(arrayToSort,String.CASE_INSENSITIVE_ORDER);

for (int i = 0; i < arrayToSort.length; i++){
System.out.print(arrayToSort[i]+",");
}
}

public static void main(String[] args) {
new Test().sortStringArray();

}

}
运行结果：
字符型数组排序,排序前:
Oscar,Charlie,Ryan,Adam,David,aff,Aff,
排序后:
Adam,aff,Aff,Charlie,David,Oscar,Ryan,
希望对你有帮助

6. JAVA编程输入三个名字按字母顺序自动排序

	publicstaticvoidmain(String[]args){
		List<String>list=newArrayList<String>();
		Scannerscan=newScanner(System.in);
		System.out.println("Pleaseinputthefirstname:");
		list.add(getName(scan.next(),"first"));
		System.out.println("Pleaseinputthesecondname:");
		list.add(getName(scan.next(),"second"));
		System.out.println("Pleaseinputthethirdname:");
		list.add(getName(scan.next(),"third"));
		scan.close();
		//剔除为null的对象（因为不合法的名称被设置为null）。
		//此处为何用ite迭代删除？原因参考http://blog.csdn.net/longyulu/article/details/8315068
		Iterator<String>ite=list.iterator();
		while(ite.hasNext()){
			Strings=ite.next();
			if(s==null){
				ite.remove();
			}
		}
		//排序
		Collections.sort(list);
		//输出最终结果
		System.out.print("Thenamesare:");
		for(Strings:list){
			System.out.print("""+s+""");
		}
		
	}

	privatestaticStringgetName(Stringname,Stringindex){
		StringregEx="^[A-Za-z]+$";//纯字母正则表达式
		Patternpat=Pattern.compile(regEx);
		if(pat.matcher(name).matches()){
			//全部转为小写
			name=name.toLowerCase();
			//提取第一个字母并转换大写
			Stringfirst=(name.charAt(0)+"").toUpperCase();
			name=first+name.substring(1);
			System.out.println(name+"isthe"+index+"name.");
		}else{
			name=null;
			System.out.println("Error:The"+index+"namewasnotaccepted.");
		}
		returnname;
	}
//控制台结果：
Pleaseinputthefirstname:
tsKd
Tskdisthefirstname.
Pleaseinputthesecondname:
ukf90
Error:Thesecondnamewasnotaccepted.
Pleaseinputthethirdname:
admin
Administhethirdname.
Thenamesare:"Admin""Tskd"

7. java字符串按照字母顺序输出，悬赏100分，在线等

单例模式

publicclassSingleConvert
{
	;
	privateStringresult;
	privateStringoriginal;

	privateSingleConvert()
	{}

	privatevoidconvertString()
	{
		charc=result.charAt(0);
		if(Character.isUpperCase(c))
		{
			System.out.println(result);
			return;
		}
		else
		{
			result=result.substring(1);
			convertString();
		}
	}

	privatevoidsortString()
	{
		char[]cs=result.toCharArray();
		for(inti=0;i<cs.length;i++)
		{
			for(intj=i+1;j<cs.length;j++)
			{
				charfirst=Character.toUpperCase(cs[i]);
				charsecond=Character.toUpperCase(cs[j]);
				if(first>second)
				{
					chartemp=cs[i];
					cs[i]=cs[j];
					cs[j]=temp;
				}
			}
		}
		result=String.valueOf(cs);
		System.out.println(result);
	}

	privatevoidfindMax()
	{
		if(result.isEmpty())
		{
			return;
		}
		Stringtemp=""+original+"";
		charmax=0;
		intnum=-1;
		for(inti=0;i<result.length();i++)
		{
			charcurrent=result.charAt(i);
			intlen=temp.split(current+"").length-1;
			if(len>num)
			{
				max=current;
				num=len;
			}
		}
		System.out.println(result+","+max+"="+num);
	}

	privatevoidrandomString(intn)
	{
		Stringresult="";
		charc='a';
		for(inti=0;i<n;i++)
		{
			intrandom=(int)(Math.random()*25);
			doubletype=Math.random();
			if(type>0.6)
			{
				result+=(char)(c+random-32);
			}
			else
			{
				result+=(char)(c+random);
			}
		}
		System.out.println(result);
		this.original=result;
		this.result=result;
	}

	()
	{
		if(null==singleConvert)
		{
			singleConvert=newSingleConvert();
		}
		returnsingleConvert;
	}

	publicstaticvoidmain(String[]args)
	{
		SingleConvertsingleConvert=SingleConvert.getInstance();
		singleConvert.randomString(13);
		singleConvert.convertString();
		singleConvert.sortString();
		singleConvert.findMax();
	}
}

8. JAVA 通过字符串的split方法,按照空格拆分字符串,之后按首字母排序

public static void main(String args[])
{
String target="John Bill Peter ";

ArrayList<String> list=new ArrayList<String>();
for(String temp:target.split(" "))
{
list.add(temp);
}

Collections.sort(list);

for(String temp:list)
{
System.out.print(temp+" ");
}

}

9. java中怎样把输入的基本英文单词按首字母顺序排列

importjava.util.ArrayList;
importjava.util.Collections;
importjava.util.Comparator;
importjava.util.List;

/**
*规则：大写字母前于小写字母
*
*@authorAdministrator
*
*/
publicclassSortWords{

privatestaticfinalString[]array={"A","B","C","D","E","F","G",
"H","I","J","K","L","M","N","O","P","Q","R","S","T",
"U","V","W","X","Y","Z"};

publicstaticvoidmain(String[]args){
SortWordssw=newSortWords();
List<String>words=newArrayList<String>();
words.add("book");
words.add("ear");
words.add("alert");
words.add("choice");
words.add("name");
words.add("memery");
words.add("fight");
words.add("call");
words.add("joy");
List<String>list=sw.sort(words,"forward");
for(Stringstr:list){
System.out.println(str);
}
}

publicList<String>sort(List<String>words,Stringtype){
List<Word>list=newArrayList<Word>();
List<String>res=newArrayList<String>();
for(Stringword:words){
Wordw=indexNum(word);
list.add(w);
}
switch(type){
case"forward":
Collections.sort(list,newForward());
for(Wordw:list){
res.add(w.getContent());
}
break;
case"back":
Collections.sort(list,newBack());
for(Wordw:list){
res.add(w.getContent());
}
break;
}

returnres;
}

publicWordindexNum(Stringword){
String[]letters=word.split("");
Stringres="";
Wordw=newWord();
Stringletter=word.substring(0,1);
for(inti=0;i<array.length;i++){
Stringpattern=array[i];
if(letter.equalsIgnoreCase(pattern)){
res+=i;
break;
}
}
w.setContent(word);
w.setIndexNum(Integer.parseInt(res));
returnw;
}

{
@Override
publicintcompare(Objectarg0,Objectarg1){
Wordw1=(Word)arg0;
Wordw2=(Word)arg1;
intflag=w1.getIndexNum()-w2.getIndexNum();
returnflag;
}
}

{
@Override
publicintcompare(Objectarg0,Objectarg1){
Wordw1=(Word)arg1;
Wordw2=(Word)arg0;
intflag=w1.getIndexNum()-w2.getIndexNum();
returnflag;
}
}
}

classWord{
privateStringcontent;

privateIntegerindexNum;

publicStringgetContent(){
returncontent;
}

publicvoidsetContent(Stringcontent){
this.content=content;
}

publicIntegergetIndexNum(){
returnindexNum;
}

publicvoidsetIndexNum(IntegerindexNum){
this.indexNum=indexNum;
}

}