拼音转汉字、SpEL表达式、汉字转拼音

一、SpEL语法案例

import org.springframework.expression.Expression;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.StandardEvaluationContext;
import org.springframework.util.PropertyPlaceholderHelper;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.*;

public class PlaceholderResolver {

    public static void main(String[] args) throws NoSuchMethodException {
        ExpressionParser parser = new SpelExpressionParser();
       //字符串解析
        String str = (String) parser.parseExpression("'你好'").getValue();
        System.out.println(str);
        //整型解析
        int intVal = (Integer) parser.parseExpression("0x2F").getValue();
        System.out.println(intVal);
        //双精度浮点型解析
        double doubleVal = (Double) parser.parseExpression("4329759E+22").getValue();
        System.out.println(doubleVal);
        //布尔型解析
        boolean booleanVal = (boolean) parser.parseExpression("true").getValue();
        System.out.println(booleanVal);
        //执行表达式，默认容器是spring本身的容器：ApplicationContext
        List<Integer> result1 = parser.parseExpression("{1,2,3}").getValue(List.class);
        //等同于如下java代码
        Integer[] integer = new Integer[]{1,2,3};
        List<Integer> result2 = Arrays.asList(integer);
        //创建ctx容器
        StandardEvaluationContext ctx = new StandardEvaluationContext();
        //获取java自带的Integer类的parseInt(String)方法
        Method parseInt = Integer.class.getDeclaredMethod("parseInt", String.class);
        //将parseInt方法注册在ctx容器内, 推荐这样使用
        ctx.registerFunction("parseInt", parseInt);
        //再将parseInt方法设为parseInt2
        ctx.setVariable("parseInt2", parseInt);
        //创建ExpressionParser解析表达式
        ExpressionParser parsers = new SpelExpressionParser();
        //SpEL语法，比对两个方法执行完成后，结果是否相同
        String expressionString = "#parseInt('2') == #parseInt2('3')";
        //执行SpEL
        Expression expression = parsers.parseExpression(expressionString);
        Boolean values = expression.getValue(ctx, Boolean.class);
        System.out.println(values);
    }


    private static final PropertyPlaceholderHelper defaultHelper = new PropertyPlaceholderHelper("${", "}");
    private static PlaceholderResolver defaultResolver = new PlaceholderResolver();

    private PropertyPlaceholderHelper propertyPlaceholderHelper;


    private PlaceholderResolver() {
        propertyPlaceholderHelper = defaultHelper;
    }

    private PlaceholderResolver(String placeholderPrefix, String placeholderSuffix) {
        propertyPlaceholderHelper = new PropertyPlaceholderHelper(placeholderPrefix, placeholderSuffix);
    }

    /**
     * 获取默认的占位符解析器，即占位符前缀为"${", 后缀为"}"
     *
     * @return
     */
    public static PlaceholderResolver getDefaultResolver() {
        return defaultResolver;
    }

    public static PlaceholderResolver getResolver(String placeholderPrefix, String placeholderSuffix) {
        return new PlaceholderResolver(placeholderPrefix, placeholderSuffix);
    }

    /**
     * 解析带有指定占位符的模板字符串
     * 如：content =  ${0}今年${1}岁

     * values = {"xiaoming", "18"}

     * result 小明今年18岁

     *
     * @param content 要解析的带有占位符的模板字符串
     * @param values  按照模板占位符索引位置设置对应的值
     * @return
     */
    public String resolve(String content, String... values) {
        return propertyPlaceholderHelper.replacePlaceholders(content, placeholderName -> {
            return values[Integer.valueOf(placeholderName)];
        });
    }

    /**
     * 解析带有指定占位符的模板字符串
     * 如：content =  ${0}今年${1}岁

     * values = {"xiaoming", "18"}

     * result 小明今年18岁

     *
     * @param content 要解析的带有占位符的模板字符串
     * @param values  按照模板占位符索引位置设置对应的值
     * @return
     */
    public String resolve(String content, Object[] values) {
        return propertyPlaceholderHelper.replacePlaceholders(content, placeholderName -> {
            return String.valueOf(values[Integer.valueOf(placeholderName)]);
        });
    }

    /**
     * 根据替换规则来替换指定模板中的占位符值
     *
     * @param content             要解析的字符串
     * @param placeholderResolver 解析规则回调
     * @return
     */
    public String resolveByRule(String content, PropertyPlaceholderHelper.PlaceholderResolver placeholderResolver) {
        return propertyPlaceholderHelper.replacePlaceholders(content, placeholderResolver);
    }

    /**
     * 替换模板中占位符内容，占位符的内容即为map key对应的值，key为占位符中的内容。


     * 如：content = ${name}今年${age}岁

     * valueMap = name -> 小明; age -> 18

     * result 小明今年18岁

     *
     * @param content  模板内容。
     * @param valueMap 值映射
     * @return 替换完成后的字符串。
     */
    public String resolveByMap(String content, final Map<String, Object> valueMap) {
        return propertyPlaceholderHelper.replacePlaceholders(content, placeholderName -> {
            return String.valueOf(valueMap.get(placeholderName));
        });
    }

    /**
     * 根据对象中字段路径(即类似js访问对象属性值)替换模板中的占位符 


     * 如 content = product:${id}:detail:${detail.id} 

     * obj = Product.builder().id(1).detail(Detail.builder().id(2).build()).build(); 

     * 经过解析返回 product:1:detail:2 

     *
     * @param content 要解析的内容
     * @param obj     填充解析内容的对象(如果是基本类型，则所有占位符都替换为当前基本类型)
     * @return
     */
    public String resolveByObject(String content, final Object obj) {
        if (obj instanceof Map) {
            return resolveByMap(content, (Map) obj);
        }
        return propertyPlaceholderHelper.replacePlaceholders(content, placeholderName -> {
            return String.valueOf(getValueByFieldPath(obj, placeholderName));
        });
    }

    /**
     * 获取指定对象中指定字段路径的值
     * $(user.name)
     *
     * @param obj       取值对象
     * @param fieldPath 字段路径(形如 user.name)
     * @return
     */
    private Object getValueByFieldPath(Object obj, String fieldPath) {
        String[] fieldNames = fieldPath.split("\\.");
        Object result = null;
        for (String fieldName : fieldNames) {
            result = getFieldValue(obj, fieldName);
            if (result == null) {
                throw new RuntimeException(fieldName + "为空！");
            }
            obj = result;
        }
        return result;
    }

    private Object getFieldValue(Object obj, String fieldName) {
        Class clazz = obj.getClass();
        if (isBaseType(clazz)) {
            return obj;
        }
        while (clazz != Object.class && clazz != null) {
            try {
                Field field = clazz.getDeclaredField(fieldName);
                field.setAccessible(true);
                return field.get(obj);
            } catch (NoSuchFieldException e) {
                clazz = clazz.getSuperclass();
            } catch (IllegalAccessException e) {
                throw new RuntimeException("无法访问 " + fieldName);
            }
        }
        throw new IllegalStateException(fieldName + "字段不存在！");

    }

    /**
     * 判断class是否为常用类型
     *
     * @param clazz
     * @return
     */
    private boolean isBaseType(Class clazz) {
        return Enum.class.isAssignableFrom(clazz) || CharSequence.class.isAssignableFrom(clazz)
                || Number.class.isAssignableFrom(clazz) || Date.class.isAssignableFrom(clazz);
    }



    /**
     * 打码隐藏加*
     *
     * @param num   号码
     * @param front 需要显示前几位
     * @param end   需要显示末几位
     * @return
     */
    public static String mask(String num, int front, int end) {
        // 传入的号码不能为空
        if (num == null || num.length() <= 0) {
            return null;
        }
        // 需要截取的长度不能大于号码长度
        if ((front + end) > num.length()) {
            return null;
        }
        //需要截取的不能小于0
        if (front < 0 || end < 0) {
            return null;
        }
        //计算*的数量
        int asteriskCount = num.length() - (front + end);
        StringBuffer asteriskStr = new StringBuffer();
        for (int i = 0; i < asteriskCount; i++) {
            asteriskStr.append("*");
        }
        String regex = "(\\w{" + front + "})(\\w+)(\\w{" + end + "})";
        // $1、$2、……表示正则表达式里面第一个、第二个、……括号里面的匹配内容
        return num.replaceAll(regex, "$1" + asteriskStr + "$3");
    }
}

二、汉字转拼音

       <dependency>
            <groupId>com.belerweb</groupId>
            <artifactId>pinyin4j</artifactId>
            <version>2.5.0</version>
        </dependency>
       <dependency>
	       <groupId>com.github.stuxuhai</groupId>
	       <artifactId>jpinyin</artifactId>
	       <version>1.1.7</version>
       </dependency>

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;

import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import net.sourceforge.pinyin4j.PinyinHelper;
import net.sourceforge.pinyin4j.format.HanyuPinyinCaseType;
import net.sourceforge.pinyin4j.format.HanyuPinyinOutputFormat;
import net.sourceforge.pinyin4j.format.HanyuPinyinToneType;
import net.sourceforge.pinyin4j.format.HanyuPinyinVCharType;
import net.sourceforge.pinyin4j.format.exception.BadHanyuPinyinOutputFormatCombination;

@Slf4j
public class Pinyin4jUtil {

    /**
     * getFirstSpellPinYin:(多音字的时候获取第一个). 

     * @param src  传入的拼音字符串，以逗号隔开
     * @param isFullSpell 是否全拼，true:全拼，false:第一个汉字全拼(其它汉字取首字母)
     * @return 第一个拼音
     */
    public static String getFirstSpellPinYin(String src, boolean isFullSpell) {
        String targetStr = Pinyin4jUtil.makeStringByStringSet(Pinyin4jUtil.getPinyin(src, isFullSpell));
        String[] split = targetStr.split(",");
        if (split.length > 1) {
            targetStr = split[0];
        }
        return targetStr;
    }

    /**
     * makeStringByStringSet:(拼音字符串集合转换字符串(逗号分隔)). 

     * @param stringSet  拼音集合
     * @return  带逗号字符串
     */
    public static String makeStringByStringSet(Set<String> stringSet) {
        StringBuilder str = new StringBuilder();
        int i = 0;
        if (stringSet.size() > 0) {
            for (String s : stringSet) {
                if (i == stringSet.size() - 1) {
                    str.append(s);
                } else {
                    str.append(s + ",");
                }
                i++;
            }
        }
        return str.toString().toLowerCase();
    }

    /**
     * getPinyin:(获取汉字拼音). 

     * @param src   汉字
     * @param isFullSpell  是否全拼,如果为true：全拼，false:首字全拼
     * @return
     */
    public static Set<String> getPinyin(String src, boolean isFullSpell) {
        if (src != null && !src.trim().equalsIgnoreCase("")) {
            char[] srcChar;
            srcChar = src.toCharArray();
            // 汉语拼音格式输出类
            HanyuPinyinOutputFormat hanYuPinOutputFormat = new HanyuPinyinOutputFormat();
            // 输出设置，大小写，音标方式等
            hanYuPinOutputFormat.setCaseType(HanyuPinyinCaseType.LOWERCASE);
            hanYuPinOutputFormat.setToneType(HanyuPinyinToneType.WITHOUT_TONE);
            hanYuPinOutputFormat.setVCharType(HanyuPinyinVCharType.WITH_V);
            String[][] temp = new String[src.length()][];
            for (int i = 0; i < srcChar.length; i++) {
                char c = srcChar[i];
                if (String.valueOf(c).matches("[\\u4E00-\\u9FA5]+")) {
                    //中文
                    try {
                        temp[i] = PinyinHelper.toHanyuPinyinStringArray(
                                srcChar[i], hanYuPinOutputFormat);
                        if (!isFullSpell) {
                            if (i == 0) {
                                temp[i] = temp[i];
                            } else {
                                String[] tTemps = new String[temp[i].length];
                                for (int j = 0; j < temp[i].length; j++) {
                                    char t = temp[i][j].charAt(0);
                                    tTemps[j] = Character.toString(t);
                                }
                                temp[i] = tTemps;
                            }
                        }
                    } catch (BadHanyuPinyinOutputFormatCombination e) {
                        e.printStackTrace();
                    }
                    //英文
                } else if (((int) c >= 65 && (int) c <= 90)
                        || ((int) c >= 97 && (int) c <= 122)) {
                    temp[i] = new String[] { String.valueOf(srcChar[i]) };
                } else {
                    temp[i] = new String[] { "" };
                }
            }
            String[] pingyinArray = exchange(temp);
            Set<String> pinyinSet = new HashSet<>();
            for (int i = 0; i < pingyinArray.length; i++) {
                pinyinSet.add(pingyinArray[i]);
            }
            return pinyinSet;
        }
        return null;
    }

    /**
     * 递归
     * @param strJaggedArray
     * @return
     */
    public static String[] exchange(String[][] strJaggedArray) {
        String[][] temp = doExchange(strJaggedArray);
        return temp[0];
    }

    /**
     * 递归
     * @param strJaggedArray
     * @return
     */
    private static String[][] doExchange(String[][] strJaggedArray) {
        int len = strJaggedArray.length;
        if (len >= 2) {
            int len1 = strJaggedArray[0].length;
            int len2 = strJaggedArray[1].length;
            int newlen = len1 * len2;
            String[] temp = new String[newlen];
            int Index = 0;
            for (int i = 0; i < len1; i++) {
                for (int j = 0; j < len2; j++) {
                    temp[Index] = strJaggedArray[0][i] + strJaggedArray[1][j];
                    Index++;
                }
            }
            String[][] newArray = new String[len - 1][];
            for (int i = 2; i < len; i++) {
                newArray[i - 1] = strJaggedArray[i];
            }
            newArray[0] = temp;
            return doExchange(newArray);
        } else {
            return strJaggedArray;
        }
    }

    /**
     * 判断是否是中文字符串 还是拼音或者英文字符串
     * @param str
     * @return
     */
    public static boolean isChinese(String str){
        String regEx = "[\\u4e00-\\u9fa5]+";
        Pattern p = Pattern.compile(regEx);
        Matcher m = p.matcher(str);
        return m.find();
    }


    /**
     * 将字符串转换成拼音数组
     *
     * @param src
     * @return
     */
    public static String[] stringToPinyin(String src) {
        return stringToPinyin(src, false, null);
    }

    /**
     * 将字符串转换成拼音数组
     *
     * @param src
     * @return
     */
    public static String[] stringToPinyin(String src, String separator) {
        return stringToPinyin(src, true, separator);
    }

    /**
     * 将字符串转换成拼音数组
     *
     * @param src
     * @param isPolyphone
     *            是否查出多音字的所有拼音
     * @param separator
     *            多音字拼音之间的分隔符
     * @return
     */
    public static String[] stringToPinyin(String src, boolean isPolyphone,
                                          String separator) {
        // 判断字符串是否为空
        if ("".equals(src) || null == src) {
            return null;
        }
        char[] srcChar = src.toCharArray();
        int srcCount = srcChar.length;
        String[] srcStr = new String[srcCount];
        for (int i = 0; i < srcCount; i++) {
            srcStr[i] = charToPinyin(srcChar[i], isPolyphone, separator);
        }
        return srcStr;
    }

    /**
     * 将单个字符转换成拼音
     *
     * @param src
     * @return
     */
    public static String charToPinyin(char src, boolean isPolyphone, String separator) {
        // 创建汉语拼音处理类
        HanyuPinyinOutputFormat defaultFormat = new HanyuPinyinOutputFormat();
        // 输出设置，大小写，音标方式
        defaultFormat.setCaseType(HanyuPinyinCaseType.LOWERCASE);
        defaultFormat.setToneType(HanyuPinyinToneType.WITHOUT_TONE);
        StringBuffer tempPinying = new StringBuffer();
        // 如果是中文
        if (src > 128) {
            try {
                // 转换得出结果
                String[] strs = PinyinHelper.toHanyuPinyinStringArray(src, defaultFormat);
                // 是否查出多音字，默认是查出多音字的第一个字符
                if (isPolyphone && null != separator) {
                    for (int i = 0; i < strs.length; i++) {
                        tempPinying.append(strs[i]);
                        if (strs.length != (i + 1)) {
                            // 多音字之间用特殊符号间隔起来
                            tempPinying.append(separator);
                        }
                    }
                } else {
                    tempPinying.append(strs[0]);
                }
            } catch (BadHanyuPinyinOutputFormatCombination e) {
               log.error("中文转拼音错误：{}",e);
            }
        } else {
            tempPinying.append(src);
        }
        return tempPinying.toString();
    }


    public static void main(String[] args) {
        System.out.println(isChinese("你好呀"));
        System.out.println(JSON.toJSONString(stringToPinyin("你好呀")));
        String string =  Arrays.asList(stringToPinyin("你好呀")).stream().collect(Collectors.joining(" "));
        System.out.println(string);
    }





}

三、拼音转汉字

1、原理是viterbi算法、原理是词库+动态规划、搜狗语料库

参考：https://github.com/ranchlai/pinyin2hanzi
2、喵搜输入法

参考：https://github.com/crownpku/Somiao-Pinyin

3、隐马尔科夫模型(HMM)实现的拼音转汉字

参考：https://github.com/KHN190/pinyin