1 /*
2 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package jdk.packager.services.userjvmoptions;
27
28 import jdk.packager.services.UserJvmOptionsService;
29
30 import java.security.AllPermission;
31 import java.util.LinkedHashMap;
32 import java.util.LinkedList;
33 import java.util.List;
34 import java.util.Map;
35
36 /**
37 *
38 * Access the UserJVMOptions via a native library provided by the launcher.
39 *
40 * Do not instantiate this class directly, instead use
41 * {@see jdk.packager.services.UserJvmOptionsService#getUserJVMDefaults()}
42 * to get an instance.
43 *
44 * @since 8u40
45 */
46 final public class LauncherUserJvmOptions implements UserJvmOptionsService {
47
48 private static final Object semaphore = new Object();
49
50 static {
51 try {
52 checkAllPermissions();
53 System.loadLibrary("packager");
54 } catch (SecurityException se) {
55 // fail to load, we will also throw on all public methods
56 }
57 }
58
59 private static void checkAllPermissions() {
60 final SecurityManager securityManager = System.getSecurityManager();
61 if (securityManager != null) {
62 securityManager.checkPermission(new AllPermission());
63 }
64 }
65
66 /**
67 * Access the default User JVM Option for a specific key
68 *
69 * @param option the key for the User JVM Option
70 *
71 * @return the default value of the user JVM Option. Currently set user
72 * values are not considered, and only the default is returned. If there
73 * is no default value then null is returned.
74 */
75 private static native String _getUserJvmOptionDefaultValue(String option);
76
77 /**
78 * This lists the keys for User JVM Options that will have a default
79 * provided by the launcher.
80 *
81 * This list will be a subset of the keys used by the launcher and only
82 * lists those values that will have a default value provided if the user
83 * does not set a value of their own.
84 *
85 * @return an array of keys in no particular order.
86 */
87 private static native String[] _getUserJvmOptionDefaultKeys();
88 /**
89 * Access the current User JVM Option for a specific key
90 *
91 * @param option the key for the User JVM Option
92 *
93 * @return the current value of the user JVM Option. If the user has not
94 * set a value then the default value is returned, except in the case where
95 * there is no default value, where null is returned.
96 */
97 private static native String _getUserJvmOptionValue(String option);
98
99 /**
100 * Update the all User JVM Options
101 *
102 * All option/value pairs will be replaced with the values provided. The
103 * parameters options and values are paired at the same index.
104 * Example: options[3] = -Xmx and values[3] = 999m
105 * This cannot be used to adjust default values.
106 *
107 * @param options the keys for the User JVM Options
108 * @param values the values for the User JVM Options
109 */
110 private static native void _setUserJvmKeysAndValues(String[] options, String[] values);
111
112 /**
113 * This lists the keys for all User JVM Options that will be used by the
114 * launcher.
115 *
116 * This list will be a superset of the defaults as may also include user
117 * values that do not have a default.
118 *
119 * @return an array of keys in no particular order.
120 */
121 private static native String[] _getUserJvmOptionKeys();
122
123 @Override
124 public Map<String, String> getUserJVMOptions() {
125 checkAllPermissions();
126 synchronized (semaphore) {
127 Map<String, String> results = new LinkedHashMap<>();
128 for (String s : _getUserJvmOptionKeys()) {
129 results.put(s, _getUserJvmOptionValue(s));
130 }
131 return results;
132 }
133 }
134
135 @Override
136 public void setUserJVMOptions(Map<String, String> options) {
137 checkAllPermissions();
138 synchronized (semaphore) {
139 List<String> keys = new LinkedList<>();
140 List<String> values = new LinkedList<>();
141
142 for (Map.Entry<String, String> option : options.entrySet()) {
143 if (option.getKey() == null) {
144 throw new IllegalArgumentException("For Launcher Backed UserJVMOptions keys in the UserJVMOptions map cannot be null.");
145 }
146 if (option.getValue() == null) {
147 throw new IllegalArgumentException("For Launcher Backed UserJVMOptions values in the UserJVMOptions map cannot be null. Keys are removed by absence, not by setting keys to null.");
148 }
149 keys.add(option.getKey());
150 values.add(option.getValue());
151 }
152
153 _setUserJvmKeysAndValues(keys.toArray(new String[keys.size()]),
154 values.toArray(new String[values.size()]));
155 }
156 }
157
158 @Override
159 public Map<String, String> getUserJVMOptionDefaults() {
160 checkAllPermissions();
161 synchronized (semaphore) {
162 Map<String, String> results = new LinkedHashMap<>();
163 for (String s : _getUserJvmOptionDefaultKeys()) {
164 results.put(s, _getUserJvmOptionDefaultValue(s));
165 }
166 return results;
167 }
168 }
169 }