<?xml version="1.0" encoding="UTF-8"?>
<users xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="users.xsd">
	<user id="id0">
		<firstName>asd</firstName>
		<lastName>asd</lastName>
		<email>asdasd@asd.com<;/email>
		<password>asdasd</password>
	</user>
</users>

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
	<xs:element name="users">
		<xs:complexType>
			<xs:sequence>
				<xs:element maxOccurs="unbounded" ref="user" />
			</xs:sequence>
		</xs:complexType>
	</xs:element>
	<xs:element name="user">
		<xs:complexType>
			<xs:sequence>
				<xs:element name="first_name" type="xs:NCName" />
				<xs:element name="last_name" type="xs:NCName" />
				<xs:element name="email" type="Email" />
				<xs:element name="password" type="Password" />
			</xs:sequence>
			<xs:attribute name="id" type="xs:ID" use="required" />
		</xs:complexType>

	</xs:element>
	<xs:simpleType name="Email">
		<xs:restriction base="xs:string">
			<xs:pattern value="паттерн" />
		</xs:restriction>
	</xs:simpleType>
	<xs:simpleType name="Password">
		<xs:restriction base="xs:string">
			<xs:pattern value="паттерн" />
		</xs:restriction>
	</xs:simpleType>
</xs:schema>

public static boolean validateXml(File xml, File xsd) {
    try {
        SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI)
                .newSchema(new StreamSource(xsd))
                .newValidator()
                .validate(new StreamSource(xml));
    } catch (Exception e) {
        return false;
    }
    return true;
}