java - hbase:根据输入值分配 CompareFilter.CompareOp

Question

我们可以根据输入值取 compareOperator 值吗？例如，如果我的输入是 eq，那么它应该选择 CompareFilter.CompareOp.EQUAL，否则如果输入是 ne，它应该选择 CompareFilter.CompareOp.NOT_EQUAL.

有点像

if(input.equals("eq")) {
    myCompareOp = EQUAL;
}else if(input.equals("ne")) {
    myCompareOp = NOT_EQUAL;
}

SingleColumnValueFilter colValFilter = new SingleColumnValueFilter(Bytes.toBytes(<CF>), Bytes.toBytes(<CQ>)
                , myCompareOp, new BinaryComparator(Bytes.toBytes(<value>)));

任何建议将不胜感激

Answer 1

基于上面的代码，是的，它会起作用。下面是示例代码片段，你也可以看看。其中 ConditionType 是枚举...这样你也可以准备自己的枚举(如果条件也可以，则不是强制性的)

private Filter buildSimpleQuery(ConditionType ct, String name, Object value) {
    name = super.getRealPropertyName(name);
    validatePropertyValue(name, value);
    Class<?> clazz = getPrimitiveFieldClass(name, value.getClass());
    CompareOp compareOp = null;
    boolean regexCompRequired = false;
    switch (ct) {
    case EQUALS:
        compareOp = CompareOp.EQUAL;
        regexCompRequired = String.class == clazz && value.toString().endsWith("*");
        break;
    case NOT_EQUALS:
        compareOp = CompareOp.NOT_EQUAL;
        regexCompRequired = String.class == clazz && value.toString().endsWith("*");
        break;
    case GREATER_THAN:
        compareOp = CompareOp.GREATER;
        break;
    case GREATER_OR_EQUALS:
        compareOp = CompareOp.GREATER_OR_EQUAL;
        break;
    case LESS_THAN:
        compareOp = CompareOp.LESS;
        break;
    case LESS_OR_EQUALS:
        compareOp = CompareOp.LESS_OR_EQUAL;
        break;
    default: 
        break;
    }
    String qualifier = name;
    String theFamily = family != null ? family : familyMap.get(qualifier);
    ByteArrayComparable byteArrayComparable = regexCompRequired 
        ? new RegexStringComparator(value.toString().replace("*", "."))
        : new BinaryComparator(value.toString().getBytes(StandardCharsets.UTF_8));

    Filter query = new SingleColumnValueFilter(theFamily.getBytes(StandardCharsets.UTF_8),
                                               qualifier.getBytes(StandardCharsets.UTF_8),
                                               compareOp,
                                               byteArrayComparable);
    return query;
}