1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 package org.apache.commons.exec.environment;
19
20 import java.io.BufferedReader;
21 import java.io.IOException;
22 import java.util.HashMap;
23 import java.util.Map;
24 import java.util.TreeMap;
25
26 import org.apache.commons.exec.CommandLine;
27 import org.apache.commons.exec.OS;
28
29 /**
30 * Helper class to determine the environment variable for the OS. Depending on the JDK the environment variables can be either retrieved directly from the JVM
31 * or requires starting a process to get them running an OS command line.
32 */
33 public class DefaultProcessingEnvironment {
34
35 /** The environment variables of the process */
36 protected Map<String, String> procEnvironment;
37
38 /**
39 * Creates a map that obeys the casing rules of the current platform for key lookup. E.g. on a Windows platform, the map keys will be case-insensitive.
40 *
41 * @return The map for storage of environment variables, never {@code null}.
42 */
43 private Map<String, String> createEnvironmentMap() {
44 if (OS.isFamilyWindows()) {
45 return new TreeMap<>(String::compareToIgnoreCase);
46 }
47 return new HashMap<>();
48 }
49
50 /**
51 * Creates the list of environment variables for this process.
52 *
53 * @return a amp containing the environment variables.
54 * @throws IOException the operation failed.
55 */
56 protected Map<String, String> createProcEnvironment() throws IOException {
57 if (procEnvironment == null) {
58 procEnvironment = createEnvironmentMap();
59 procEnvironment.putAll(System.getenv());
60 }
61 return procEnvironment;
62 }
63
64 /**
65 * Determine the OS specific command line to get a list of environment variables.
66 *
67 * @return the command line.
68 * @deprecated No longer needed.
69 */
70 @Deprecated
71 protected CommandLine getProcEnvCommand() {
72 // String executable;
73 // String[] arguments = null;
74 // if (OS.isFamilyOS2()) {
75 // // OS/2 - use same mechanism as Windows 2000
76 // executable = "cmd";
77 //
78 // arguments = new String[] {"/c", "set"};
79 // } else if (OS.isFamilyWindows()) {
80 // // Determine if we're running under XP/2000/NT or 98/95
81 // if (OS.isFamilyWin9x()) {
82 // executable = "command.com";
83 // // Windows 98/95
84 // } else {
85 // executable = "cmd";
86 // // Windows XP/2000/NT/2003
87 // }
88 // arguments = new String[] {"/c", "set"};
89 // } else if (OS.isFamilyZOS() || OS.isFamilyUnix()) {
90 // // On most systems one could use: /bin/sh -c env
91 //
92 // // Some systems have /bin/env, others /usr/bin/env, just try
93 // if (new File("/bin/env").canRead()) {
94 // executable = "/bin/env";
95 // } else if (new File("/usr/bin/env").canRead()) {
96 // executable = "/usr/bin/env";
97 // } else {
98 // // rely on PATH
99 // executable = "env";
100 // }
101 // } else if (OS.isFamilyNetware() || OS.isFamilyOS400()) {
102 // // rely on PATH
103 // executable = "env";
104 // } else {
105 // // macOS 9 and previous
106 // // TODO: I have no idea how to get it, someone must fix it
107 // executable = null;
108 // }
109 final CommandLine commandLine = null;
110 // if (executable != null) {
111 // commandLine = new CommandLine(executable);
112 // commandLine.addArguments(arguments);
113 // }
114 return commandLine;
115 }
116
117 /**
118 * Gets the list of environment variables for this process.
119 *
120 * @return a map containing the environment variables.
121 * @throws IOException obtaining the environment variables failed.
122 */
123 public synchronized Map<String, String> getProcEnvironment() throws IOException {
124 if (procEnvironment == null) {
125 procEnvironment = this.createProcEnvironment();
126 }
127 // create a copy of the map just in case that
128 // anyone is going to modifiy it, e.g. removing
129 // or setting an evironment variable
130 final Map<String, String> copy = createEnvironmentMap();
131 copy.putAll(procEnvironment);
132 return copy;
133 }
134
135 /**
136 * Runs a process to list the environment variables.
137 *
138 * @return a reader containing the output of the process.
139 * @throws IOException starting the process failed.
140 * @deprecated No longer needed.
141 */
142 @Deprecated
143 protected BufferedReader runProcEnvCommand() throws IOException {
144 // final ByteArrayOutputStream out = new ByteArrayOutputStream();
145 // final Executor exe = DefaultExecutor.builder().get();
146 // exe.setStreamHandler(new PumpStreamHandler(out));
147 // // ignore the exit value - Just try to use what we got
148 // exe.execute(getProcEnvCommand());
149 // return new BufferedReader(new StringReader(toString(out)));
150 return null;
151 }
152
153 }