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/lang/BootstrapMethodError.java

/*
 * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.lang;

/**
 * Thrown to indicate that an {@code invokedynamic} instruction has
 * failed to find its bootstrap method,
 * or the bootstrap method has failed to provide a
 * {@linkplain java.lang.invoke.CallSite call site} with a {@linkplain java.lang.invoke.CallSite#getTarget target}
 * of the correct {@linkplain java.lang.invoke.MethodHandle#type method type}.
 *
 * @author John Rose, JSR 292 EG
 * @since 1.7
 */
public class BootstrapMethodError extends LinkageError {
    private static final long serialVersionUID = 292L;

    /**
     * Constructs a {@code BootstrapMethodError} with no detail message.
     */
    public BootstrapMethodError() {
        super();
    }

    /**
     * Constructs a {@code BootstrapMethodError} with the specified
     * detail message.
     *
     * @param s the detail message.
     */
    public BootstrapMethodError(String s) {
        super(s);
    }

    /**
     * Constructs a {@code BootstrapMethodError} with the specified
     * detail message and cause.
     *
     * @param s the detail message.
     * @param cause the cause, may be {@code null}.
     */
    public BootstrapMethodError(String s, Throwable cause) {
        super(s, cause);
    }

    /**
     * Constructs a {@code BootstrapMethodError} with the specified
     * cause.
     *
     * @param cause the cause, may be {@code null}.
     */
    public BootstrapMethodError(Throwable cause) {
        // cf. Throwable(Throwable cause) constructor.
        super(cause == null ? null : cause.toString());
        initCause(cause);
    }
}

⏎ java/lang/BootstrapMethodError.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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