https://xerces.apache.org/xerces2-j/: Xerces2 is the next generation of high performance, fully compliant XML parsers in the Apache Xerces family. This new version of Xerces introduces the Xerces Native Interface (XNI), a complete framework for building parser components and configurations that is extremely modular and easy to program. The Apache Xerces2 parser is the reference implementation of XNI but other parser components, configurations, and parsers can be written using the Xerces Native Interface. For complete design and implementation documents, refer to the XNI Manual. Xerces2 is a fully conforming XML Schema 1.0 processor. A partial experimental implementation of the XML Schema 1.1 Structures and Datatypes Working Drafts (December 2009) and an experimental implementation of the XML Schema Definition Language (XSD): Component Designators (SCD) Candidate Recommendation (January 2010) are provided for evaluation. For more information, refer to the XML Schema page. Xerces2 also provides a complete implementation of the Document Object Model Level 3 Core and Load/Save W3C Recommendations and provides a complete implementation of the XML Inclusions (XInclude) W3C Recommendation. It also provides support for OASIS XML Catalogs v1.1. Xerces2 is able to parse documents written according to the XML 1.1 Recommendation, except that it does not yet provide an option to enable normalization checking as described in section 2.13 of this specification. It also handles namespaces according to the XML Namespaces 1.1 Recommendation, and will correctly serialize XML 1.1 documents if the DOM level 3 load/save APIs are in use. 
public class org.apache.xerces.impl.Version
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: org.apache.xerces.impl.Version
  super_class: java.lang.Object
{
  public static java.lang.String fVersion;
    descriptor: Ljava/lang/String;
    flags: (0x0009) ACC_PUBLIC, ACC_STATIC

  private static final java.lang.String fImmutableVersion;
    descriptor: Ljava/lang/String;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: "@@VERSION@@"

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 33
            ldc "@@VERSION@@"
            putstatic org.apache.xerces.impl.Version.fVersion:Ljava/lang/String;
         1: .line 35
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // org.apache.xerces.impl.Version this
         0: .line 25
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // org.apache.xerces.impl.Version this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/apache/xerces/impl/Version;

  public static java.lang.String getVersion();
    descriptor: ()Ljava/lang/String;
    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 43
            ldc "@@VERSION@@"
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public static void main(java.lang.String[]);
    descriptor: ([Ljava/lang/String;)V
    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // java.lang.String[] argv
         0: .line 55
            getstatic java.lang.System.out:Ljava/io/PrintStream;
            getstatic org.apache.xerces.impl.Version.fVersion:Ljava/lang/String;
            invokevirtual java.io.PrintStream.println:(Ljava/lang/String;)V
         1: .line 56
            return
        end local 0 // java.lang.String[] argv
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  argv  [Ljava/lang/String;
    MethodParameters:
      Name  Flags
      argv  
}
SourceFile: "Version.java"