Java 11 and later, Java 17 or Kotlin
To configure your Maven project, add the following code to your pom.xml file:
<dependencies>
<dependency>
<groupId>com.github.javadev</groupId>
<artifactId>underscore</artifactId>
<version>1.111</version>
</dependency>
...
</dependencies>Gradle configuration:
implementation 'com.github.javadev:underscore:1.111'U.of(/* array | list | set | map | anything based on Iterable interface */)
.filter(..)
.map(..)
...
.sortWith()
.forEach(..);
U.of(value1, value2, value3)...
U.range(0, 10)...
U.of(1, 2, 3) // or java.util.Arrays.asList(1, 2, 3) or new Integer[] {1, 2, 3}
.filter(v -> v > 1)
// 2, 3
.map(v -> v + 1)
// 3, 4
.sortWith((a, b) -> b.compareTo(a))
.forEach(System.out::println);
// 4, 3
U.of(1, 2, 3) // or java.util.Arrays.asList(1, 2, 3) or new Integer[] {1, 2, 3}
.mapMulti((num, consumer) -> {
for (int i = 0; i < num; i++) {
consumer.accept("a" + num);
}
})
.forEach(System.out::println);
// "a1", "a2", "a2", "a3", "a3", "a3"
U.formatXml("<a><b>data</b></a>", Xml.XmlStringBuilder.Step.TWO_SPACES);
// <a>
// <b>data</b>
// </a>
U.formatJson("{\"a\":{\"b\":\"data\"}}", Json.JsonStringBuilder.Step.TWO_SPACES);
// {
// "a": {
// "b": "data"
// }
// }
U.xmlToJson(
"<mydocument has=\"an attribute\">\n"
+ " <and>\n"
+ " <many>elements</many>\n"
+ " <many>more elements</many>\n"
+ " </and>\n"
+ " <plus a=\"complex\">\n"
+ " element as well\n"
+ " </plus>\n"
+ "</mydocument>",
Json.JsonStringBuilder.Step.TWO_SPACES);
// {
// "mydocument": {
// "-has": "an attribute",
// "and": {
// "many": [
// "elements",
// "more elements"
// ]
// },
// "plus": {
// "-a": "complex",
// "#text": "\n element as well\n "
// }
// },
// "#omit-xml-declaration": "yes"
// }
U.xmlToJsonMinimum(
"<data>\n"
+ " <string>Example Text</string>\n"
+ " <integer>42</integer>\n"
+ " <float>3.14</float>\n"
+ " <boolean>true</boolean>\n"
+ " <date>2025-02-26</date>\n"
+ " <time>14:30:00</time>\n"
+ " <datetime>2025-02-26T14:30:00Z</datetime>\n"
+ " <array>Item 1</array>\n"
+ " <array>Item 2</array>\n"
+ " <object>\n"
+ " <key1>Value 1</key1>\n"
+ " <key2>Value 2</key2>\n"
+ " </object>\n"
+ " <null/>\n"
+ "</data>\n",
Json.JsonStringBuilder.Step.TWO_SPACES);
// {
// "data": {
// "string": "Example Text",
// "integer": "42",
// "float": "3.14",
// "boolean": "true",
// "date": "2025-02-26",
// "time": "14:30:00",
// "datetime": "2025-02-26T14:30:00Z",
// "array": [
// "Item 1",
// "Item 2"
// ],
// "object": {
// "key1": "Value 1",
// "key2": "Value 2"
// },
// "null": ""
// }
// }
U.jsonToXml(
"{\n"
+ " \"mydocument\": {\n"
+ " \"-has\": \"an attribute\",\n"
+ " \"and\": {\n"
+ " \"many\": [\n"
+ " \"elements\",\n"
+ " \"more elements\"\n"
+ " ]\n"
+ " },\n"
+ " \"plus\": {\n"
+ " \"-a\": \"complex\",\n"
+ " \"#text\": \"\\n element as well\\n \"\n"
+ " }\n"
+ " },\n"
+ " \"#omit-xml-declaration\": \"yes\"\n"
+ "}",
Xml.XmlStringBuilder.Step.TWO_SPACES);
// <mydocument has="an attribute">
// <and>
// <many>elements</many>
// <many>more elements</many>
// </and>
// <plus a="complex">
// element as well
// </plus>
// </mydocument>
U.jsonToXmlMinimum(
"{\n"
+ " \"data\": {\n"
+ " \"string\": \"Example Text\",\n"
+ " \"integer\": \"42\",\n"
+ " \"float\": \"3.14\",\n"
+ " \"boolean\": \"true\",\n"
+ " \"date\": \"2025-02-26\",\n"
+ " \"time\": \"14:30:00\",\n"
+ " \"datetime\": \"2025-02-26T14:30:00Z\",\n"
+ " \"array\": [\n"
+ " \"Item 1\",\n"
+ " \"Item 2\"\n"
+ " ],\n"
+ " \"object\": {\n"
+ " \"key1\": \"Value 1\",\n"
+ " \"key2\": \"Value 2\"\n"
+ " },\n"
+ " \"null\": \"\"\n"
+ " }\n"
+ "}",
Xml.XmlStringBuilder.Step.TWO_SPACES);
// <data>
// <string>Example Text</string>
// <integer>42</integer>
// <float>3.14</float>
// <boolean>true</boolean>
// <date>2025-02-26</date>
// <time>14:30:00</time>
// <datetime>2025-02-26T14:30:00Z</datetime>
// <array>Item 1</array>
// <array>Item 2</array>
// <object>
// <key1>Value 1</key1>
// <key2>Value 2</key2>
// </object>
// <null string="true"/>
// </data>
U.Builder builder = U.objectBuilder()
.add("firstName", "John")
.add("lastName", "Smith")
.add("age", 25)
.add("address", U.arrayBuilder()
.add(U.objectBuilder()
.add("streetAddress", "21 2nd Street")
.add("city", "New York")
.addNull("cityId")
.add("state", "NY")
.add("postalCode", "10021")))
.add("phoneNumber", U.arrayBuilder()
.add(U.objectBuilder()
.add("type", "home")
.add("number", "212 555-1234"))
.add(U.objectBuilder()
.add("type", "fax")
.add("number", "646 555-4567")));
System.out.println(builder.toJson());
System.out.println(builder.toXml());{
"firstName": "John",
"lastName": "Smith",
"age": 25,
"address": [
{
"streetAddress": "21 2nd Street",
"city": "New York",
"cityId": null,
"state": "NY",
"postalCode": "10021"
}
],
"phoneNumber": [
{
"type": "home",
"number": "212 555-1234"
},
{
"type": "fax",
"number": "646 555-4567"
}
]
}<?xml version="1.0" encoding="UTF-8"?>
<root>
<firstName>John</firstName>
<lastName>Smith</lastName>
<age number="true">25</age>
<address array="true">
<streetAddress>21 2nd Street</streetAddress>
<city>New York</city>
<cityId null="true"/>
<state>NY</state>
<postalCode>10021</postalCode>
</address>
<phoneNumber>
<type>home</type>
<number>212 555-1234</number>
</phoneNumber>
<phoneNumber>
<type>fax</type>
<number>646 555-4567</number>
</phoneNumber>
</root>Simplify XML document creation by structuring your code like the final document.
This code:
XmlBuilder builder = XmlBuilder.create("Projects")
.e("underscore-java").a("language", "Java").a("scm", "SVN")
.e("Location").a("type", "URL")
.t("https://github.com/javadev/underscore-java/")
.up()
.up()
.e("JetS3t").a("language", "Java").a("scm", "CVS")
.e("Location").a("type", "URL")
.t("https://jets3t.s3.amazonaws.com/index.html");
System.out.println(builder.toXml(Xml.XmlStringBuilder.Step.TWO_SPACES));
System.out.println(builder.toJson(Json.JsonStringBuilder.Step.TWO_SPACES));Generates the following XML and JSON documents:
<?xml version="1.0" encoding="UTF-8"?>
<Projects>
<underscore-java language="Java" scm="SVN">
<Location type="URL">https://github.com/javadev/underscore-java/</Location>
</underscore-java>
<JetS3t language="Java" scm="CVS">
<Location type="URL">https://jets3t.s3.amazonaws.com/index.html</Location>
</JetS3t>
</Projects>{
"Projects": {
"underscore-java": {
"-language": "Java",
"-scm": "SVN",
"Location": {
"-type": "URL",
"#text": "https://github.com/javadev/underscore-java/"
}
},
"JetS3t": {
"-language": "Java",
"-scm": "CVS",
"Location": {
"-type": "URL",
"#text": "https://jets3t.s3.amazonaws.com/index.html"
}
}
}
}Underscore-java is a java port of Underscore.js.
In addition to porting Underscore's functionality, Underscore-java includes matching unit tests.
For docs, license, tests, and downloads, see: https://javadev.github.io/underscore-java
Thanks to Jeremy Ashkenas and all contributors to Underscore.js.
