XML 配置继承，避免重复 [英] XML configuration inheritance, avoid duplications

问题描述

想象一下，当您有大约 10 多个几乎相同的多个环境的大型 XML 配置文件时.

Imagine a situation when you have about 10+ big XML configuration files for multiple environments which are almost identical.

有时您必须添加一个新选项，这会导致修改所有具有相同数据的 10..20..30+ 个文件.

Sometimes you have to add a new option, which leads to modification of all those 10..20..30+ files with the same data.

你犯了错误.与其他分支合并时会发生冲突.你变得紧张和沮丧.

You make mistakes. You get conflicts when merging with other branches. You got nervous and depressed.

有什么好的工具可以为纯 XML 文件(不是 Spring.cgf 或 POM)提供类似继承的功能?

Are there any good tools that provide something like inheritance for plain XML files (not Spring.cgf or POM)?

或者我必须自己编写一个 ant 或 maven 自行车脚本?

Or I have to write an ant or maven bicycle-script on my own?

推荐答案

您可以使用实体/实体引用在多个位置、文件内或文件间引用和重用内容.

You can use entities/entity references for referencing and reusing content at multiple places, within or across files.

声明和使用实体的 XML 文件如下所示:

An XML file declaring and using an entity looks like this:

<!DOCTYPE doc [
  <!ENTITY myent "<x>Text content of myent</x>">
]>
<doc>
  &myent;
  &myent;
</doc>

这个 XML 文件被处理

This XML file is handled as if

<doc>
  <x>Text content of myent</x>
  <x>Text content of myent</x>
</doc>

已被指定.也就是说，实体引用 &myent; 被替换为它的替换文本 <x>myent</x> 的文本内容.

had been specified. That is, the entity reference &myent; is substituted by its replacement text <x>Text content of myent</x>.

这也适用于存储在外部文件(称为外部实体)中的替换文本.假设上面的文件存储为 doc.xml，您可以从另一个 XML 文件中引用它，如下所示:

This works also with replacement text stored in an external file (called an external entity). Assuming the file above is stored as doc.xml, you can reference it from another XML file like this:

<!DOCTYPE otherdoc [
  <!ENTITY doc SYSTEM "doc.xml">
]>
<otherdoc>
  &doc;
</otherdoc>

XML 解析器会将其视为好像

and an XML parser will treat it as if

<otherdoc>
  <doc>
    <x>Text content of myent</x>
    <x>Text content of myent</x>
  </doc>
</otherdoc>

已被指定.

使用实体，您可以组织常见的 XML 内容，而不会在文件内或文件之间产生冗余.希望有所帮助.

Using entities, you can organize common XML content without redundancy within or accross files. Hope that helps.

请注意，您必须调整 DOCTYPE - 它必须与您的 XML 的文档元素相匹配

note that you have to adapt the DOCTYPE - it must match the document element of your XML

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