JDK 11 java.base.jmod is the JMOD file for JDK 11 Base module.

JDK 11 Base module compiled class files are stored in \fyicenter\jdk-11.0.1\jmods\java.base.jmod.

JDK 11 Base module compiled class files are also linked and stored in the \fyicenter\jdk-11.0.1\lib\modules JImage file.

JDK 11 Base module source code files are stored in \fyicenter\jdk-11.0.1\lib\src.zip\java.base.

You can click and view the content of each source code file in the list below.

⏎ jdk/internal/module/Checks.java

/*
 * Copyright (c) 2009, 2017, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
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 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */

package jdk.internal.module;

import java.util.Set;

/**
 * Utility class for checking module, package, and class names.
 */

public final class Checks {

    private Checks() { }

    /**
     * Checks a name to ensure that it's a legal module name.
     *
     * @throws IllegalArgumentException if name is null or not a legal
     *         module name
     */
    public static String requireModuleName(String name) {
        if (name == null)
            throw new IllegalArgumentException("Null module name");
        int next;
        int off = 0;
        while ((next = name.indexOf('.', off)) != -1) {
            String id = name.substring(off, next);
            if (!isJavaIdentifier(id)) {
                throw new IllegalArgumentException(name + ": Invalid module name"
                        + ": '" + id + "' is not a Java identifier");
            }
            off = next+1;
        }
        String last = name.substring(off);
        if (!isJavaIdentifier(last)) {
            throw new IllegalArgumentException(name + ": Invalid module name"
                    + ": '" + last + "' is not a Java identifier");
        }
        return name;
    }

    /**
     * Returns {@code true} if the given name is a legal module name.
     */
    public static boolean isModuleName(String name) {
        int next;
        int off = 0;
        while ((next = name.indexOf('.', off)) != -1) {
            String id = name.substring(off, next);
            if (!isJavaIdentifier(id))
                return false;
            off = next+1;
        }
        String last = name.substring(off);
        return isJavaIdentifier(last);
    }

    /**
     * Checks a name to ensure that it's a legal package name.
     *
     * @throws IllegalArgumentException if name is null or not a legal
     *         package name
     */
    public static String requirePackageName(String name) {
        return requireTypeName("package name", name);
    }

    /**
     * Returns {@code true} if the given name is a legal package name.
     */
    public static boolean isPackageName(String name) {
        return isTypeName(name);
    }

    /**
     * Checks a name to ensure that it's a legal qualified class name
     *
     * @throws IllegalArgumentException if name is null or not a legal
     *         qualified class name
     */
    public static String requireServiceTypeName(String name) {
        return requireQualifiedClassName("service type name", name);
    }

    /**
     * Checks a name to ensure that it's a legal qualified class name.
     *
     * @throws IllegalArgumentException if name is null or not a legal
     *         qualified class name
     */
    public static String requireServiceProviderName(String name) {
        return requireQualifiedClassName("service provider name", name);
    }

    /**
     * Checks a name to ensure that it's a legal qualified class name in
     * a named package.
     *
     * @throws IllegalArgumentException if name is null or not a legal
     *         qualified class name in a named package
     */
    public static String requireQualifiedClassName(String what, String name) {
        requireTypeName(what, name);
        if (name.indexOf('.') == -1)
            throw new IllegalArgumentException(name + ": is not a qualified name of"
                                               + " a Java class in a named package");
        return name;
    }

    /**
     * Returns {@code true} if the given name is a legal class name.
     */
    public static boolean isClassName(String name) {
        return isTypeName(name);
    }

    /**
     * Returns {@code true} if the given name is a legal type name.
     */
    private static boolean isTypeName(String name) {
        int next;
        int off = 0;
        while ((next = name.indexOf('.', off)) != -1) {
            String id = name.substring(off, next);
            if (!isJavaIdentifier(id))
                return false;
            off = next+1;
        }
        String last = name.substring(off);
        return isJavaIdentifier(last);
    }

    /**
     * Checks if the given name is a legal type name.
     *
     * @throws IllegalArgumentException if name is null or not a legal
     *         type name
     */
    private static String requireTypeName(String what, String name) {
        if (name == null)
            throw new IllegalArgumentException("Null " + what);
        int next;
        int off = 0;
        while ((next = name.indexOf('.', off)) != -1) {
            String id = name.substring(off, next);
            if (!isJavaIdentifier(id)) {
                throw new IllegalArgumentException(name + ": Invalid " + what
                        + ": '" + id + "' is not a Java identifier");
            }
            off = next + 1;
        }
        String last = name.substring(off);
        if (!isJavaIdentifier(last)) {
            throw new IllegalArgumentException(name + ": Invalid " + what
                    + ": '" + last + "' is not a Java identifier");
        }
        return name;
    }

    /**
     * Returns true if the given char sequence is a legal Java identifier,
     * otherwise false.
     */
    private static boolean isJavaIdentifier(CharSequence cs) {
        if (cs.length() == 0 || RESERVED.contains(cs))
            return false;

        int first = Character.codePointAt(cs, 0);
        if (!Character.isJavaIdentifierStart(first))
            return false;

        int i = Character.charCount(first);
        while (i < cs.length()) {
            int cp = Character.codePointAt(cs, i);
            if (!Character.isJavaIdentifierPart(cp))
                return false;
            i += Character.charCount(cp);
        }

        return true;
    }

    // keywords, boolean and null literals, not allowed in identifiers
    private static final Set<String> RESERVED = Set.of(
            "abstract",
            "assert",
            "boolean",
            "break",
            "byte",
            "case",
            "catch",
            "char",
            "class",
            "const",
            "continue",
            "default",
            "do",
            "double",
            "else",
            "enum",
            "extends",
            "final",
            "finally",
            "float",
            "for",
            "goto",
            "if",
            "implements",
            "import",
            "instanceof",
            "int",
            "interface",
            "long",
            "native",
            "new",
            "package",
            "private",
            "protected",
            "public",
            "return",
            "short",
            "static",
            "strictfp",
            "super",
            "switch",
            "synchronized",
            "this",
            "throw",
            "throws",
            "transient",
            "try",
            "void",
            "volatile",
            "while",
            "true",
            "false",
            "null",
            "_"
    );
}

⏎ jdk/internal/module/Checks.java

Or download all of them as a single archive file:

File name: java.base-11.0.1-src.zip
File size: 8740354 bytes
Release date: 2018-11-04
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