Package org.apache.logging.log4j.core.layout

Class XmlLayout

  • All Implemented Interfaces:
    LocationAware, Layout<java.lang.String>, Encoder<LogEvent>, StringLayout
    @Plugin(name="XmlLayout",
        category="Core",
        elementType="layout",
        printObject=true)
public final class XmlLayout
extends AbstractJacksonLayout
    Appends a series of event elements as defined in the log4j.dtd.

    Complete well-formed XML vs. fragment XML

    If you configure complete="true", the appender outputs a well-formed XML document where the default namespace is the log4j namespace "http://logging.apache.org/log4j/2.0/events". By default, with complete="false", you should include the output as an external entity in a separate file to form a well-formed XML document.

    If complete="false", the appender does not write the XML processing instruction and the root element.

    Encoding

    Appenders using this layout should have their charset set to UTF-8 or UTF-16, otherwise events containing non-ASCII characters could result in corrupted log files.

    Pretty vs. compact XML

    By default, the XML layout is not compact (compact = not "pretty") with compact="false", which means the appender uses end-of-line characters and indents lines to format the XML. If compact="true", then no end-of-line or indentation is used. Message content may contain, of course, end-of-lines.

    Additional Fields

    This property allows addition of custom fields into generated JSON. <XmlLayout><KeyValuePair key="foo" value="bar"/></XmlLayout> inserts <foo>bar</foo> directly into XML output. Supports Lookup expressions.

    • Constructor Detail

      • XmlLayout

        @Deprecated
protected XmlLayout​(boolean locationInfo,
                    boolean properties,
                    boolean complete,
                    boolean compact,
                    java.nio.charset.Charset charset,
                    boolean includeStacktrace)
        Deprecated.
        Use newBuilder() instead

      • XmlLayout

        private XmlLayout​(Configuration config,
                  boolean locationInfo,
                  boolean properties,
                  boolean complete,
                  boolean compact,
                  java.lang.String endOfLine,
                  java.nio.charset.Charset charset,
                  boolean includeStacktrace,
                  boolean stacktraceAsString,
                  boolean includeNullDelimiter,
                  boolean includeTimeMillis,
                  KeyValuePair[] additionalFields)

    • Method Detail

      • getHeader

        public byte[] getHeader()
        Returns appropriate XML headers.
        1. XML processing instruction
        2. XML root element
        Specified by:
        getHeader in interface Layout<java.lang.String>
        Overrides:
        getHeader in class AbstractStringLayout
        Returns:
        a byte array containing the header.

      • getFooter

        public byte[] getFooter()
        Returns appropriate XML footer.
        Specified by:
        getFooter in interface Layout<java.lang.String>
        Overrides:
        getFooter in class AbstractStringLayout
        Returns:
        a byte array containing the footer, closing the XML root element.

      • getContentFormat

        public java.util.Map<java.lang.String,​java.lang.String> getContentFormat()
        Gets this XmlLayout's content format. Specified by:
        • Key: "dtd" Value: "log4j-events.dtd"
        • Key: "version" Value: "2.0"
        Specified by:
        getContentFormat in interface Layout<java.lang.String>
        Overrides:
        getContentFormat in class AbstractLayout<java.lang.String>
        Returns:
        Map of content format keys supporting XmlLayout

      • getContentType

        public java.lang.String getContentType()
        Description copied from interface: Layout
        Returns the content type output by this layout. The base class returns "text/plain".
        Specified by:
        getContentType in interface Layout<java.lang.String>
        Overrides:
        getContentType in class AbstractStringLayout
        Returns:
        The content type.

      • createLayout

        @Deprecated
public static XmlLayout createLayout​(boolean locationInfo,
                                     boolean properties,
                                     boolean complete,
                                     boolean compact,
                                     java.nio.charset.Charset charset,
                                     boolean includeStacktrace)
        Deprecated.
        Use newBuilder() instead
        Creates an XML Layout.
        Parameters:
        locationInfo - If "true", includes the location information in the generated XML.
        properties - If "true", includes the thread context map in the generated XML.
        complete - If "true", includes the XML header and footer, defaults to "false".
        compact - If "true", does not use end-of-lines and indentation, defaults to "false".
        charset - The character set to use, if null, uses "UTF-8".
        includeStacktrace - If "true", includes the stacktrace of any Throwable in the generated XML, defaults to "true".
        Returns:
        An XML Layout.

      • createDefaultLayout

        public static XmlLayout createDefaultLayout()
        Creates an XML Layout using the default settings.
        Returns:
        an XML Layout.