JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries. JRE (Java Runtime) 8 is the runtime environment included in JDK 8. JRE 8 rt.jar libraries are divided into 6 packages:

com.* - Internal Oracle and Sun Microsystems libraries
java.* - Standard Java API libraries.
javax.* - Extended Java API libraries.
jdk.* -  JDK supporting libraries.
org.* - Third party libraries.
sun.* - Old libraries developed by Sun Microsystems.

JAR File Information:

Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
      63,596,151 rt.jar

Here is the list of Java classes of the java.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ java/sql/Struct.java

/*
 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.sql;

/**
 * <p>The standard mapping in the Java programming language for an SQL
 * structured type. A <code>Struct</code> object contains a
 * value for each attribute of the SQL structured type that
 * it represents.
 * By default, an instance of<code>Struct</code> is valid as long as the
 * application has a reference to it.
 * <p>
 * All methods on the <code>Struct</code> interface must be fully implemented if the
 * JDBC driver supports the data type.
 * @since 1.2
 */

public interface Struct {

  /**
   * Retrieves the SQL type name of the SQL structured type
   * that this <code>Struct</code> object represents.
   *
   * @return the fully-qualified type name of the SQL structured
   *          type for which this <code>Struct</code> object
   *          is the generic representation
   * @exception SQLException if a database access error occurs
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  String getSQLTypeName() throws SQLException;

  /**
   * Produces the ordered values of the attributes of the SQL
   * structured type that this <code>Struct</code> object represents.
   * As individual attributes are processed, this method uses the type map
   * associated with the
   * connection for customizations of the type mappings.
   * If there is no
   * entry in the connection's type map that matches the structured
   * type that an attribute represents,
   * the driver uses the standard mapping.
   * <p>
   * Conceptually, this method calls the method
   * <code>getObject</code> on each attribute
   * of the structured type and returns a Java array containing
   * the result.
   *
   * @return an array containing the ordered attribute values
   * @exception SQLException if a database access error occurs
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  Object[] getAttributes() throws SQLException;

  /**
   * Produces the ordered values of the attributes of the SQL
   * structured type that this <code>Struct</code> object represents.
   *  As individual attributes are processed, this method uses the given type map
   * for customizations of the type mappings.
   * If there is no
   * entry in the given type map that matches the structured
   * type that an attribute represents,
   * the driver uses the standard mapping. This method never
   * uses the type map associated with the connection.
   * <p>
   * Conceptually, this method calls the method
   * <code>getObject</code> on each attribute
   * of the structured type and returns a Java array containing
   * the result.
   *
   * @param map a mapping of SQL type names to Java classes
   * @return an array containing the ordered attribute values
   * @exception SQLException if a database access error occurs
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  Object[] getAttributes(java.util.Map<String,Class<?>> map)
      throws SQLException;
}

⏎ java/sql/Struct.java

Or download all of them as a single archive file:

File name: jre-rt-java-1.8.0_191-src.zip
File size: 6664831 bytes
Release date: 2018-10-28
Download 

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