--- /dev/null	2019-02-07 20:54:51.336000000 +0300
+++ new/test/lib/jdk/test/lib/Asserts.java	2019-02-08 18:33:57.343330138 +0300
@@ -0,0 +1,620 @@
+/*
+ * Copyright (c) 2013, 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.test.lib;
+
+import java.util.Objects;
+
+/**
+ * Asserts that can be used for verifying assumptions in tests.
+ *
+ * An assertion will throw a {@link RuntimeException} if the assertion isn't true.
+ * All the asserts can be imported into a test by using a static import:
+ *
+ * <pre>
+ * {@code
+ * import static jdk.testlibrary.Asserts.*;
+ * }
+ *
+ * Always provide a message describing the assumption if the line number of the
+ * failing assertion isn't enough to understand why the assumption failed. For
+ * example, if the assertion is in a loop or in a method that is called
+ * multiple times, then the line number won't provide enough context to
+ * understand the failure.
+ * </pre>
+ */
+public class Asserts {
+
+    /**
+     * Shorthand for {@link #assertLessThan(Comparable, Comparable)}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertLessThan(Comparable, Comparable)
+     */
+    public static <T extends Comparable<T>> void assertLT(T lhs, T rhs) {
+        assertLessThan(lhs, rhs);
+    }
+
+    /**
+     * Shorthand for {@link #assertLessThan(Comparable, Comparable, String)}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @see #assertLessThan(Comparable, Comparable, String)
+     */
+    public static <T extends Comparable<T>> void assertLT(T lhs, T rhs, String msg) {
+        assertLessThan(lhs, rhs, msg);
+    }
+
+    /**
+     * Calls {@link #assertLessThan(Comparable, Comparable, String)} with a default message.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertLessThan(Comparable, Comparable, String)
+     */
+    public static <T extends Comparable<T>> void assertLessThan(T lhs, T rhs) {
+        assertLessThan(lhs, rhs, null);
+    }
+
+    /**
+     * Asserts that {@code lhs} is less than {@code rhs}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static <T extends Comparable<T>>void assertLessThan(T lhs, T rhs, String msg) {
+        if (!(compare(lhs, rhs, msg) < 0)) {
+            msg = Objects.toString(msg, "assertLessThan")
+                    + ": expected that " + Objects.toString(lhs)
+                    + " < " + Objects.toString(rhs);
+            fail(msg);
+        }
+    }
+
+    /**
+     * Shorthand for {@link #assertLessThanOrEqual(Comparable, Comparable)}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertLessThanOrEqual(Comparable, Comparable)
+     */
+    public static <T extends Comparable<T>> void assertLTE(T lhs, T rhs) {
+        assertLessThanOrEqual(lhs, rhs);
+    }
+
+    /**
+     * Shorthand for {@link #assertLessThanOrEqual(Comparable, Comparable, String)}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @see #assertLessThanOrEqual(Comparable, Comparable, String)
+     */
+    public static <T extends Comparable<T>> void assertLTE(T lhs, T rhs, String msg) {
+        assertLessThanOrEqual(lhs, rhs, msg);
+    }
+
+    /**
+     * Calls {@link #assertLessThanOrEqual(Comparable, Comparable, String)} with a default message.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertLessThanOrEqual(Comparable, Comparable, String)
+     */
+    public static <T extends Comparable<T>> void assertLessThanOrEqual(T lhs, T rhs) {
+        assertLessThanOrEqual(lhs, rhs, null);
+    }
+
+    /**
+     * Asserts that {@code lhs} is less than or equal to {@code rhs}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static <T extends Comparable<T>> void assertLessThanOrEqual(T lhs, T rhs, String msg) {
+        if (!(compare(lhs, rhs, msg) <= 0)) {
+            msg = Objects.toString(msg, "assertLessThanOrEqual")
+                    + ": expected that " + Objects.toString(lhs)
+                    + " <= " + Objects.toString(rhs);
+            fail(msg);
+        }
+    }
+
+    /**
+     * Shorthand for {@link #assertEquals(Object, Object)}.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertEquals(Object, Object)
+     */
+    public static void assertEQ(Object lhs, Object rhs) {
+        assertEquals(lhs, rhs);
+    }
+
+    /**
+     * Shorthand for {@link #assertEquals(Object, Object, String)}.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @see #assertEquals(Object, Object, String)
+     */
+    public static void assertEQ(Object lhs, Object rhs, String msg) {
+        assertEquals(lhs, rhs, msg);
+    }
+
+    /**
+     * Calls {@link #assertEquals(java.lang.Object, java.lang.Object, java.lang.String)} with a default message.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertEquals(Object, Object, String)
+     */
+    public static void assertEquals(Object lhs, Object rhs) {
+        assertEquals(lhs, rhs, null);
+    }
+
+    /**
+     * Asserts that {@code lhs} is equal to {@code rhs}.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static void assertEquals(Object lhs, Object rhs, String msg) {
+        if ((lhs != rhs) && ((lhs == null) || !(lhs.equals(rhs)))) {
+            msg = Objects.toString(msg, "assertEquals")
+                    + ": expected " + Objects.toString(lhs)
+                    + " to equal " + Objects.toString(rhs);
+            fail(msg);
+        }
+    }
+
+    /**
+     * Calls {@link #assertSame(java.lang.Object, java.lang.Object, java.lang.String)} with a default message.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertSame(Object, Object, String)
+     */
+    public static void assertSame(Object lhs, Object rhs) {
+        assertSame(lhs, rhs, null);
+    }
+
+    /**
+     * Asserts that {@code lhs} is the same as {@code rhs}.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static void assertSame(Object lhs, Object rhs, String msg) {
+        if (lhs != rhs) {
+            msg = Objects.toString(msg, "assertSame")
+                    + ": expected " + Objects.toString(lhs)
+                    + " to equal " + Objects.toString(rhs);
+            fail(msg);
+        }
+    }
+
+    /**
+     * Shorthand for {@link #assertGreaterThanOrEqual(Comparable, Comparable)}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertGreaterThanOrEqual(Comparable, Comparable)
+     */
+    public static <T extends Comparable<T>> void assertGTE(T lhs, T rhs) {
+        assertGreaterThanOrEqual(lhs, rhs);
+    }
+
+    /**
+     * Shorthand for {@link #assertGreaterThanOrEqual(Comparable, Comparable, String)}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @see #assertGreaterThanOrEqual(Comparable, Comparable, String)
+     */
+    public static <T extends Comparable<T>> void assertGTE(T lhs, T rhs, String msg) {
+        assertGreaterThanOrEqual(lhs, rhs, msg);
+    }
+
+    /**
+     * Calls {@link #assertGreaterThanOrEqual(Comparable, Comparable, String)} with a default message.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertGreaterThanOrEqual(Comparable, Comparable, String)
+     */
+    public static <T extends Comparable<T>> void assertGreaterThanOrEqual(T lhs, T rhs) {
+        assertGreaterThanOrEqual(lhs, rhs, null);
+    }
+
+    /**
+     * Asserts that {@code lhs} is greater than or equal to {@code rhs}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static <T extends Comparable<T>> void assertGreaterThanOrEqual(T lhs, T rhs, String msg) {
+        if (!(compare(lhs, rhs, msg) >= 0)) {
+            msg = Objects.toString(msg, "assertGreaterThanOrEqual")
+                    + ": expected " + Objects.toString(lhs)
+                    + " >= " + Objects.toString(rhs);
+            fail(msg);
+        }
+    }
+
+    /**
+     * Shorthand for {@link #assertGreaterThan(Comparable, Comparable)}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertGreaterThan(Comparable, Comparable)
+     */
+    public static <T extends Comparable<T>> void assertGT(T lhs, T rhs) {
+        assertGreaterThan(lhs, rhs);
+    }
+
+    /**
+     * Shorthand for {@link #assertGreaterThan(Comparable, Comparable, String)}.
+     *
+     * @param <T> a type
+     * @param lhs the left hand value
+     * @param rhs the right hand value
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @see #assertGreaterThan(Comparable, Comparable, String)
+     */
+    public static <T extends Comparable<T>> void assertGT(T lhs, T rhs, String msg) {
+        assertGreaterThan(lhs, rhs, msg);
+    }
+
+    /**
+     * Calls {@link #assertGreaterThan(Comparable, Comparable, String)} with a default message.
+     *
+     * @param <T> a type
+     * @param lhs the left hand value
+     * @param rhs the right hand value
+     * @see #assertGreaterThan(Comparable, Comparable, String)
+     */
+    public static <T extends Comparable<T>> void assertGreaterThan(T lhs, T rhs) {
+        assertGreaterThan(lhs, rhs, null);
+    }
+
+    /**
+     * Asserts that {@code lhs} is greater than {@code rhs}.
+     *
+     * @param <T> a type
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static <T extends Comparable<T>> void assertGreaterThan(T lhs, T rhs, String msg) {
+        if (!(compare(lhs, rhs, msg) > 0)) {
+            msg = Objects.toString(msg, "assertGreaterThan")
+                    + ": expected " + Objects.toString(lhs)
+                    + " > " + Objects.toString(rhs);
+            fail(msg);
+        }
+    }
+
+    /**
+     * Shorthand for {@link #assertNotEquals(Object, Object)}.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertNotEquals(Object, Object)
+     */
+    public static void assertNE(Object lhs, Object rhs) {
+        assertNotEquals(lhs, rhs);
+    }
+
+    /**
+     * Shorthand for {@link #assertNotEquals(Object, Object, String)}.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @see #assertNotEquals(Object, Object, String)
+     */
+    public static void assertNE(Object lhs, Object rhs, String msg) {
+        assertNotEquals(lhs, rhs, msg);
+    }
+
+    /**
+     * Calls {@link #assertNotEquals(Object, Object, String)} with a default message.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @see #assertNotEquals(Object, Object, String)
+     */
+    public static void assertNotEquals(Object lhs, Object rhs) {
+        assertNotEquals(lhs, rhs, null);
+    }
+
+    /**
+     * Asserts that {@code lhs} is not equal to {@code rhs}.
+     *
+     * @param lhs The left hand side of the comparison.
+     * @param rhs The right hand side of the comparison.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static void assertNotEquals(Object lhs, Object rhs, String msg) {
+        if ((lhs == rhs) || (lhs != null && lhs.equals(rhs))) {
+            msg = Objects.toString(msg, "assertNotEquals")
+                    + ": expected " + Objects.toString(lhs)
+                    + " to not equal " + Objects.toString(rhs);
+            fail(msg);
+        }
+    }
+
+    /**
+     * Calls {@link #assertNull(Object, String)} with a default message.
+     *
+     * @param o The reference assumed to be null.
+     * @see #assertNull(Object, String)
+     */
+    public static void assertNull(Object o) {
+        assertNull(o, null);
+    }
+
+    /**
+     * Asserts that {@code o} is null.
+     *
+     * @param o The reference assumed to be null.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static void assertNull(Object o, String msg) {
+        assertEquals(o, null, msg);
+    }
+
+    /**
+     * Calls {@link #assertNotNull(Object, String)} with a default message.
+     *
+     * @param o The reference assumed <i>not</i> to be null,
+     * @see #assertNotNull(Object, String)
+     */
+    public static void assertNotNull(Object o) {
+        assertNotNull(o, null);
+    }
+
+    /**
+     * Asserts that {@code o} is <i>not</i> null.
+     *
+     * @param o The reference assumed <i>not</i> to be null,
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static void assertNotNull(Object o, String msg) {
+        assertNotEquals(o, null, msg);
+    }
+
+    /**
+     * Calls {@link #assertFalse(boolean, String)} with a default message.
+     *
+     * @param value The value assumed to be false.
+     * @see #assertFalse(boolean, String)
+     */
+    public static void assertFalse(boolean value) {
+        assertFalse(value, null);
+    }
+
+    /**
+     * Asserts that {@code value} is {@code false}.
+     *
+     * @param value The value assumed to be false.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static void assertFalse(boolean value, String msg) {
+        if (value) {
+            msg = Objects.toString(msg, "assertFalse")
+                    + ": expected false, was true";
+            fail(msg);
+        }
+    }
+
+    /**
+     * Calls {@link #assertTrue(boolean, String)} with a default message.
+     *
+     * @param value The value assumed to be true.
+     * @see #assertTrue(boolean, String)
+     */
+    public static void assertTrue(boolean value) {
+        assertTrue(value, null);
+    }
+
+    /**
+     * Asserts that {@code value} is {@code true}.
+     *
+     * @param value The value assumed to be true.
+     * @param msg A description of the assumption; {@code null} for a default message.
+     * @throws RuntimeException if the assertion is not true.
+     */
+    public static void assertTrue(boolean value, String msg) {
+        if (!value) {
+            msg = Objects.toString(msg, "assertTrue")
+                    + ": expected true, was false";
+            fail(msg);
+        }
+    }
+
+    private static <T extends Comparable<T>> int compare(T lhs, T rhs, String msg) {
+        if (lhs == null || rhs == null) {
+            fail(lhs, rhs, msg + ": values must be non-null:", ",");
+        }
+        return lhs.compareTo(rhs);
+    }
+
+/**
+     * Asserts that two strings are equal.
+     *
+     * If strings are not equals, then exception message
+     * will contain {@code msg} followed by list of mismatched lines.
+     *
+     * @param str1 First string to compare.
+     * @param str2 Second string to compare.
+     * @param msg A description of the assumption.
+     * @throws RuntimeException if strings are not equal.
+     */
+    public static void assertStringsEqual(String str1, String str2,
+                                          String msg) {
+        String lineSeparator = System.getProperty("line.separator");
+        String str1Lines[] = str1.split(lineSeparator);
+        String str2Lines[] = str2.split(lineSeparator);
+
+        int minLength = Math.min(str1Lines.length, str2Lines.length);
+        String longestStringLines[] = ((str1Lines.length == minLength) ?
+                                       str2Lines : str1Lines);
+
+        boolean stringsAreDifferent = false;
+
+        StringBuilder messageBuilder = new StringBuilder(msg);
+
+        messageBuilder.append("\n");
+
+        for (int line = 0; line < minLength; line++) {
+            if (!str1Lines[line].equals(str2Lines[line])) {
+                messageBuilder.append(String.
+                                      format("[line %d] '%s' differs " +
+                                             "from '%s'\n",
+                                             line,
+                                             str1Lines[line],
+                                             str2Lines[line]));
+                stringsAreDifferent = true;
+            }
+        }
+
+        if (minLength < longestStringLines.length) {
+            String stringName = ((longestStringLines == str1Lines) ?
+                                 "first" : "second");
+            messageBuilder.append(String.format("Only %s string contains " +
+                                                "following lines:\n",
+                                                stringName));
+            stringsAreDifferent = true;
+            for(int line = minLength; line < longestStringLines.length; line++) {
+                messageBuilder.append(String.
+                                      format("[line %d] '%s'", line,
+                                             longestStringLines[line]));
+            }
+        }
+
+        if (stringsAreDifferent) {
+            fail(messageBuilder.toString());
+        }
+    }
+
+    /**
+     * Returns a string formatted with a message and expected and actual values.
+     * @param lhs the actual value
+     * @param rhs  the expected value
+     * @param message the actual value
+     * @param relation the asserted relationship between lhs and rhs
+     * @return a formatted string
+     */
+    public static String format(Object lhs, Object rhs, String message, String relation) {
+        StringBuilder sb = new StringBuilder(80);
+        if (message != null) {
+            sb.append(message);
+            sb.append(' ');
+        }
+        sb.append("<");
+        sb.append(Objects.toString(lhs));
+        sb.append("> ");
+        sb.append(Objects.toString(relation, ","));
+        sb.append(" <");
+        sb.append(Objects.toString(rhs));
+        sb.append(">");
+        return sb.toString();
+    }
+
+    /**
+     * Fail reports a failure with message fail.
+     *
+     * @throws RuntimeException always
+     */
+    public static void fail() {
+        fail("fail");
+    }
+
+    /**
+     * Fail reports a failure with a message.
+     * @param message for the failure
+     * @throws RuntimeException always
+     */
+    public static void fail(String message) {
+        throw new RuntimeException(message);
+    }
+
+    /**
+     * Fail reports a failure with a formatted message.
+     *
+     * @param lhs the actual value
+     * @param rhs the expected value
+     * @param message to be format before the expected and actual values
+     * @param relation the asserted relationship between lhs and rhs
+     * @throws RuntimeException always
+     */
+    public static void fail(Object lhs, Object rhs, String message, String relation) {
+        throw new RuntimeException(format(lhs, rhs, message, relation));
+    }
+
+    /**
+     * Fail reports a failure with a message and a cause.
+     * @param message to be format before the expected and actual values
+     * @param cause the exception that caused this failure
+     * @throws RuntimeException always
+     */
+    public static void fail(String message, Throwable cause) {
+        throw new RuntimeException(message, cause);
+    }
+
+}