SQL 解析器：值类型解析设计

Posted 2022-03-12 东海陈光剑

模型设计

public class StringFieldValue extends FieldValue<String> 
    public StringFieldValue(String value) 
        this.value = value;
    

    @Override
    public String getSqlCondition() 
        return "'" + this.value + "'";
    

    @Override
    public String getQlCondition() 
        return this.value;
    

    @Override
    public String getValue() 
        return value;
    



public class DoubleFieldValue extends FieldValue<Double> 
    public DoubleFieldValue(Double value) 
        this.value = value;
    

    public DoubleFieldValue(String str)
        this(Double.valueOf(str));
    

    @Override
    public String getSqlCondition() 
        return String.valueOf(this.value);
    

    @Override
    public String getQlCondition() 
        return String.valueOf(this.value);
    

    @Override
    public Double getValue() 
        return this.value;
    



public class LongFieldValue extends FieldValue<Long> 
    public LongFieldValue(Long value) 
        this.value = value;
    

    public LongFieldValue(String str)
        this(Long.valueOf(str));
    

    @Override
    public String getSqlCondition() 
        return String.valueOf(this.value);
    

    @Override
    public String getQlCondition() 
        return String.valueOf(this.value);
    

    @Override
    public Long getValue() 
        return this.value;
    

值类型对象解析器

/**
 * 解析 fieldValue 值
 */
fun parseFieldValue(fieldCondition: FieldCondition, fieldValueType: KFieldValueType): List<FieldValue<*>?> 
    val values = fieldCondition.values
    if (values == null || values.isEmpty()) 
        ExceptionHelper.bizError("illegal value size,values length must greater than 0.")
    

    // 特征值类型
    lateinit var clazz: Class<out FieldValue<*>>
    when (fieldValueType) 
        KFieldValueType.STRING -> clazz = StringFieldValue::class.java
        KFieldValueType.LONG -> clazz = LongFieldValue::class.java
        KFieldValueType.DOUBLE -> clazz = DoubleFieldValue::class.java
        else -> ExceptionHelper.bizError("$fieldValueType fieldValueType not supported!")
    
    return FieldValue.create(clazz, *values.toTypedArray())

定义表字段的值类型

public enum KFieldValueType 

    /**
     * string类型，字符类型统一抽象为string
     */
    STRING("string"),

    /**
     * long类型，整数 & 布尔 统一抽象为long
     */
    LONG("long"),

    /**
     * double类型，浮点统一抽象为double
     */
    DOUBLE("double"),

    /**
     * map<string,string>
     */
    MAP_STRING_STRING("map_string_string"),

    /**
     * map<string,long>
     */
    MAP_STRING_LONG("map_string_long"),

    /**
     * map<string,double>
     */
    MAP_STRING_DOUBLE("map_string_double"),

    /**
     * list<string>
     */
    LIST_STRING("list_string"),


    /**
     * bitmap
     */
    BITMAP("bitmap"),

    ;


    private final String value;


    KFieldValueType(String value) 
        this.value = value;
    


    public String getValue() 
        return this.value;
    


    /**
     * 通过字符串获取标签选选项类型
     */
    public static KFieldValueType getByValue(String value) 
        if (value == null) 
            return null;
        

        for (KFieldValueType kFieldValueType : values()) 
            if (kFieldValueType.value.equalsIgnoreCase(value)) 
                return kFieldValueType;
            
        

        return null;
    



    /**
     * 类型转化为hive值类型
     */
    public String map2HiveColumnType() 
        switch (this) 
            case STRING:
                return "string";
            case LONG:
                return "bigint";
            case DOUBLE:
                return "double";
            case MAP_STRING_STRING:
                return "map<string,string>";
            case MAP_STRING_LONG:
                return "map<string,bigint>";
            case MAP_STRING_DOUBLE:
                return "map<string,double>";
            case LIST_STRING:
                return "array<string>";
            case BITMAP:
                return "array<string>";
            default:
                throw new IllegalArgumentException("FIELD TYPE NOT SUPPORT");
        
    


    /**
     * 类型转化为ch值类型
     */
    public String map2ChColumnType() 
        switch (this) 
            case STRING:
                return "String";
            case LONG:
                return "Int64";
            case DOUBLE:
                return "Float64";
            case MAP_STRING_STRING:
                return "Map(String,String)";
            case MAP_STRING_LONG:
                return "Map(String,Int64)";
            case MAP_STRING_DOUBLE:
                return "Map(String,Float64)";
            case LIST_STRING:
                return "Array(String)";
            case BITMAP:
                return "BitMap64 BitEngineEncode";

            default:
                throw ExceptionHelper.bizError("No such field type in clickhouse");
        
    

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