WSO2如何用大量数字填充属性值答案

【问题标题】：WSO2 how to pad a property value with a large quantity of digitsWSO2如何用大量数字填充属性值
【发布时间】：2020-06-22 14:08:02
【问题描述】：

我正在开发一个需要创建平面文件的 WSO2 集成 - 所以基本上，一个只有 1 列的文件，该列有 200 个字符宽，并且对于哪些值进入哪些位置有一个特定的协议。例如 -

位置 1-3 = 记录类型
位置 4 = 空格
位置 5-20 = 名字
位置 21 = 空格
位置 22-32 = 姓氏

等等等等

所以在那个例子中，姓氏有 10 个“数字”，这意味着如果这个人的姓氏是 Smith，我需要用 5 个后续的额外空格填充属性 - 比如 'Smith(后跟 5 个空格)'。我使用substring(concat('$ctx:LastName', ' '), 1, 10) 找到了简单的解决方案。这似乎适用于较小尺寸的填充占位符。但是，我遇到的问题是我填充的某些字段需要超过 100 个字符。而且我真的不想在我的单引号之间计算 100 个空格。在 WSO2 中处理这类事情有什么优雅的解决方案吗？

谢谢。

【问题讨论】：

标签： xml xpath wso2 padding

【解决方案1】：

代码：

[#assign firstName1 = "john"]
[#assign lastName1 = "doe"]
[#assign firstName2 = "abcdefghijklmnopqrstuvwxyz"]
[#assign lastName2 = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"]
[#assign firstNameMaxLength = 20]
[#assign lastNameMaxLength = 10]
[#assign placeholder = "-"]

[#function getMyProperty input outputMaxLength placeholder]
    [#if input?length > outputMaxLength]
        [#return input?substring(0,outputMaxLength)]
    [/#if]
    [#return input?right_pad(outputMaxLength,placeholder)]
[/#function]

<br>code1:${getMyProperty(firstName1,firstNameMaxLength,placeholder)}${getMyProperty(lastName1,lastNameMaxLength,placeholder)}
<br>code2:${getMyProperty(firstName2,firstNameMaxLength,placeholder)}${getMyProperty(lastName2,lastNameMaxLength,placeholder)}

输出：

code1:john----------------doe------- 
code2:abcdefghijklmnopqrstABCDEFGHIJ

【讨论】：

【解决方案2】：

基于this answer 中的方法，您可以执行以下操作：

substring(concat('Smith', string-join((1 to 50)!"_")), 1, 10)

哪些输出：

'史密斯____'

该表达式基本上创建了一个由 50 个（或任何您想要的）空格组成的字符串，将其连接到 'Smith' 并将整个内容缩减为 10 个字符。

【讨论】：

谢谢杰克，这看起来确实是我正在做的事情的完美解决方案。不过，我似乎无法让 WSO2 识别字符串连接。我在我的 synapse.properties 文件中取消了“synapse.xpath.dom.failover.enabled=true”行的注释，但是每次我尝试将其放入时，我都会收到“属性表达式的 XPath 表达式无效”。
@SeanWesche string-join() 是一种 xpath 2.0 方法。这不是我真正的领域，但似乎需要明确启用 xpath 2.0；看看这里：stackoverflow.com/a/55351665/9448090

【解决方案3】：

我最终使用了一个 smooks 调解器来处理这个问题。

<?xml version="1.0" encoding="UTF-8"?>
<localEntry key="padEntries-smooks-config" xmlns="http://ws.apache.org/ns/synapse">
    <smooks-resource-list xmlns="http://www.milyn.org/xsd/smooks-1.1.xsd" xmlns:file="http://www.milyn.org/xsd/smooks/file-routing-1.1.xsd" xmlns:fl="http://www.milyn.org/xsd/smooks/fixed-length-1.3.xsd" xmlns:ftl="http://www.milyn.org/xsd/smooks/freemarker-1.1.xsd">
        <params>
            <param name="stream.filter.type">SAX</param>
            <param name="default.serialization.on">false</param>
        </params>
        <resource-config selector="Employee180,Employee181,Employee220Domestic,Employee220Foreign,Employee240">
            <resource>org.milyn.delivery.DomModelCreator</resource>
        </resource-config>
        <ftl:freemarker applyOnElement="Employee180">
            <ftl:template>
                <!--${.vars["Employee180"].RecordType?right_pad(3)}${.vars["Employee180"].BlankSpace1?right_pad(1)}${.vars["Employee180"].ContractNumber?right_pad(6)}${.vars["Employee180"].BlankSpace2?right_pad(1)}${.vars["Employee180"].EmployeeIDNumber?right_pad(9)?replace("-","")}${.vars["Employee180"].BlankSpace3?right_pad(1)}${.vars["Employee180"].EmployeeName?right_pad(24)}${.vars["Employee180"].DateOfBirth?right_pad(10)}${.vars["Employee180"].BlankSpace4?right_pad(1)}${.vars["Employee180"].DateOfEmployment?right_pad(10)}${.vars["Employee180"].BlankSpace5?right_pad(1)}${.vars["Employee180"].Sex?right_pad(1)}${.vars["Employee180"].BlankSpace6?right_pad(8)}${.vars["Employee180"].SocialSecurityNumber?right_pad(9)}${.vars["Employee180"].BlankSpace7?right_pad(133)}${.vars["Employee180"].BenefitEventDate?right_pad(10)}${.vars["Employee180"].BlankSpace8?right_pad(5)}${.vars["Employee180"].BenefitEventReason?right_pad(4)}${.vars["Employee180"].BlankSpace9?right_pad(3)}${'\r\n'} -->
            </ftl:template>
        </ftl:freemarker>
        <ftl:freemarker applyOnElement="Employee220Domestic">
            <ftl:template>
                <!--${.vars["Employee220Domestic"].RecordType?right_pad(3)}${.vars["Employee220Domestic"].BlankSpace1?right_pad(1)}${.vars["Employee220Domestic"].ContractNumber?right_pad(6)}${.vars["Employee220Domestic"].BlankSpace2?right_pad(1)}${.vars["Employee220Domestic"].EmployeeIDNumber?right_pad(9)}${.vars["Employee220Domestic"].BlankSpace3?right_pad(1)}${.vars["Employee220Domestic"].ForeignIndicator?right_pad(1)}${.vars["Employee220Domestic"].BlankSpace4?right_pad(1)}${.vars["Employee220Domestic"].AddressLine1?right_pad(50)}${.vars["Employee220Domestic"].AddressLine2?right_pad(50)}${.vars["Employee220Domestic"].AddressLine3?right_pad(50)}${.vars["Employee220Domestic"].City?right_pad(30)}${.vars["Employee220Domestic"].State?right_pad(2)}${.vars["Employee220Domestic"].Zip?right_pad(9)}${.vars["Employee220Domestic"].BlankSpace5?right_pad(26)}${'\r\n'} -->
            </ftl:template>
        </ftl:freemarker>
        <ftl:freemarker applyOnElement="Employee220Foreign">
            <ftl:template>
                <!--${.vars["Employee220Foreign"].RecordType?right_pad(3)}${.vars["Employee220Foreign"].BlankSpace1?right_pad(1)}${.vars["Employee220Foreign"].ContractNumber?right_pad(6)}${.vars["Employee220Foreign"].BlankSpace2?right_pad(1)}${.vars["Employee220Foreign"].EmployeeIDNumber?right_pad(9)}${.vars["Employee220Foreign"].BlankSpace3?right_pad(1)}${.vars["Employee220Foreign"].ForeignIndicator?right_pad(1)}${.vars["Employee220Foreign"].BlankSpace4?right_pad(1)}${.vars["Employee220Foreign"].AddressLine1?right_pad(50)}${.vars["Employee220Foreign"].AddressLine2?right_pad(50)}${.vars["Employee220Foreign"].AddressLine3?right_pad(50)}${.vars["Employee220Foreign"].AddressLine4?right_pad(50)}${.vars["Employee220Foreign"].BlankSpace5?right_pad(17)}${'\r\n'} -->
            </ftl:template>
        </ftl:freemarker>
        <ftl:freemarker applyOnElement="Employee240">
            <ftl:template>
                <!--${.vars["Employee240"].RecordType?right_pad(3)}${.vars["Employee240"].ContractNumber?right_pad(6)}${.vars["Employee240"].EmployeeIDNumber?right_pad(9)}${.vars["Employee240"].WorkEmailAddress?right_pad(75)}${.vars["Employee240"].PersonalEmailAddress?right_pad(75)}${.vars["Employee240"].WorkPhoneNumber?right_pad(17)}${.vars["Employee240"].WorkPhoneNumberExt?right_pad(7)}${.vars["Employee240"].HomePhoneNumber?right_pad(17)}${.vars["Employee240"].HomePhoneNumberExt?right_pad(7)}${.vars["Employee240"].MobilePhoneNumber?right_pad(18)}${'\r\n'} -->
            </ftl:template>
        </ftl:freemarker>
        <ftl:freemarker applyOnElement="Employee181">
            <ftl:template>
                <!--${.vars["Employee181"].RecordType?right_pad(3)}${.vars["Employee181"].BlankSpace1?right_pad(1)}${.vars["Employee181"].ContractNumber?right_pad(6)}${.vars["Employee181"].BlankSpace2?right_pad(1)}${.vars["Employee181"].EmployeeIDNumber?right_pad(9)}${.vars["Employee181"].BlankSpace3?right_pad(1)}${.vars["Employee181"].EmployeeName?right_pad(24)}${.vars["Employee181"].BlankSpace4?right_pad(31)}${.vars["Employee181"].SocialSecurityNumber?right_pad(9)}${.vars["Employee181"].BlankSpace5?right_pad(1)}${.vars["Employee181"].RehireDate?right_pad(10)}${.vars["Employee181"].BlankSpace6?right_pad(144)}${'\r\n'} -->
            </ftl:template>
        </ftl:freemarker>
    </smooks-resource-list>
</localEntry>

【讨论】：