arrays - Groovy 简单 JSON 数组生成器

Question

我需要在 JSON 中构建一个简单的 JSON 数组，但在循环中它会在每次迭代期间覆盖第一个值。

def jsonBuilder = new groovy.json.JsonBuilder()
contact.each {
            jsonBuilder.contact(
                    FirstName:  it.getFirstName(),
                    LastName:  it.getLastName(),
                    Title: it.getTitle(),       
            )
    }

它仅返回简单的 JSON 并覆盖每次迭代的值并仅保留最后一次迭代的值。在 groovy 中构造 JSON 数组的语法是什么？

Answer 1

技巧是从联系人列表中收集。假设contract列表的结构如下，请按照下面jsonBuilder的使用方式进行操作。

def contact = [ 
    [ getFirstName : { 'A' }, getLastName : { 'B' }, getTitle : { 'C' } ], 
    [ getFirstName : { 'D' }, getLastName : { 'E' }, getTitle : { 'F' } ], 
    [ getFirstName : { 'G' }, getLastName : { 'H' }, getTitle : { 'I' } ]     
]

def jsonBuilder = new groovy.json.JsonBuilder()

jsonBuilder {
    contacts contact.collect { 
        [ 
            FirstName: it.getFirstName(), 
            LastName: it.getLastName(), 
            Title: it.getTitle() 
        ] 
    }
}

println jsonBuilder.toPrettyString()


// Prints
{
    "contacts": [
        {
            "FirstName": "A",
            "LastName": "B",
            "Title": "C"
        },
        {
            "FirstName": "D",
            "LastName": "E",
            "Title": "F"
        },
        {
            "FirstName": "G",
            "LastName": "H",
            "Title": "I"
        }
    ]
}

如果您正在寻找 JSONArray 而不是 JSONObject 作为最终结构，请使用:

jsonBuilder(
    contact.collect { 
        [ 
            FirstName: it.getFirstName(), 
            LastName: it.getLastName(), 
            Title: it.getTitle() 
        ]
    }
)

// OP
[
    {
        "FirstName": "A",
        "LastName": "B",
        "Title": "C"
    },
    {
        "FirstName": "D",
        "LastName": "E",
        "Title": "F"
    },
    {
        "FirstName": "G",
        "LastName": "H",
        "Title": "I"
    }
]

这没有意义，但如果需要如下所示的结构

[
    {
        "contact": {
            "FirstName": "A",
            "LastName": "B",
            "Title": "C"
        }
    },
    {
        "contact": {
            "FirstName": "D",
            "LastName": "E",
            "Title": "F"
        }
    },
    {
        "contact": {
            "FirstName": "G",
            "LastName": "H",
            "Title": "I"
        }
    }
]

然后使用

jsonBuilder(
    contact.collect { 
        [ 
            contact : [ 
                FirstName: it.getFirstName(), 
                LastName: it.getLastName(), 
                Title: it.getTitle() 
            ] 
        ]
    }
)