java首字母排序

1. 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+" ");
}

}

2. 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

3. 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"

4. 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;
}

}

5. java 字符串排序

//这个绝对满足您的要求
import java.util.Arrays;

public class StringSort {
public static void main(String[] args) {
String ss[]={"ab","wang","hi","a","abff"};
MyString mySs[]=new MyString[ss.length];//创建自定义排序的数组
for (int i = 0; i < ss.length; i++) {
mySs[i]=new MyString(ss[i]);
}
Arrays.sort(mySs);//排序
for (int i = 0; i < mySs.length; i++) {
System.out.println(mySs[i].s);
}
}

}

class MyString implements Comparable<MyString>{
public String s;//包装String

public MyString(String s) {
this.s = s;
}

@Override
public int compareTo(MyString o) {
if(o==null||o.s==null) return 1;
if(s.length()>o.s.length()) return 1;
else if(s.length()<o.s.length()) return -1;
return s.compareTo(o.s);
}
}

6. 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
}
}