1 | <?xml version="1.0" encoding="ISO-8859-1"?>
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2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
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3 | "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
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4 | <!ENTITY % general-entities SYSTEM "../../general.ent">
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5 | %general-entities;
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6 |
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7 | <!ENTITY anduin-download "http://anduin.linuxfromscratch.org/files/BLFS/OpenJDK-&openjdk-version;">
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8 | <!ENTITY openjdk-download-binary-x86 "&anduin-download;/OpenJDK-&openjdk-version;-i686-bin.tar.xz">
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9 | <!ENTITY openjdk-bin-md5sum-x86 "16ae4a3518def3943496006a755cd4a2">
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10 | <!ENTITY openjdk-bin-size-x86 "174 MB">
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11 | <!ENTITY openjdk-bin-buildsize-x86 "547 MB">
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12 |
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13 | <!ENTITY openjdk-download-binary-x64 "&anduin-download;/OpenJDK-&openjdk-version;-x86_64-bin.tar.xz">
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14 | <!ENTITY openjdk-bin-md5sum-x64 "d40a5a3b9f16ce8fd2fddc8866c9be00">
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15 | <!ENTITY openjdk-bin-size-x64 "218 MB">
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16 | <!ENTITY openjdk-bin-buildsize-x64 "424 MB">
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17 | ]>
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18 |
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19 | <sect1 id="java">
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20 | <?dbhtml filename="java.html"?>
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21 |
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22 | <sect1info>
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23 | <othername>$LastChangedBy$</othername>
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24 | <date>$Date$</date>
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25 | </sect1info>
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26 |
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27 | <title>About Java</title>
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28 |
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29 | <indexterm zone="java">
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30 | <primary sortas="a-java">JDK Binary</primary>
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31 | </indexterm>
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32 |
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33 |
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34 | <para>Java is different from most of the packages in LFS and BLFS. It
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35 | is a programming language that works with files of byte codes to obtain
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36 | instructions and executes then in a Java Virtual Machine (JVM). An
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37 | introductory java program looks like:</para>
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38 |
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39 | <screen><literal>public class HelloWorld
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40 | {
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41 | public static void main(String[] args)
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42 | {
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43 | System.out.println("Hello, World");
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44 | }
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45 | }</literal></screen>
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46 |
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47 | <para>This program is saved as <filename>HelloWorld.java</filename>. The file
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48 | name, <emphasis>HelloWorld</emphasis>, must match the class name. It
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49 | is then converted into byte code with <command>javac HelloWorld.java</command>.
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50 | The output file is <filename>HelloWorld.class</filename>. The program is
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51 | executed with <command>java HelloWorld</command>. This creates a JVM and
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52 | runs the code. The 'class' extension must not be specified.</para>
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53 |
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54 | <para>Several class files can be combined into one file with the
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55 | <command>jar</command> command. This is similar to the standard
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56 | <command>tar</command> command. For instance, the command <command>jar cf myjar.jar
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57 | *.class</command> will combine all class files in a directory into one jar
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58 | file. These act as library files.</para>
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59 |
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60 | <para>The JVM can search for and use classes in jar files automatically. It
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61 | uses the <envar>CLASSPATH</envar> environment variable to search for jar files.
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62 | This is a standard list of colon-separated directory names similar to
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63 | the <envar>PATH</envar> environment variable.</para>
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64 |
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65 | &lfs74_checked;
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66 |
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67 | <sect2 id="java-bin" xreflabel="Java Binary">
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68 | <title>Installing a binary JDK</title>
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69 |
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70 | <para>Creating a JVM from source requires a set of circular dependencies.
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71 | The first thing that's needed is a set of programs called a Java Development
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72 | Kit (JDK). This set of programs includes <command>java</command>,
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73 | <command>javac</command>, <command>jar</command>, and severl others. It
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74 | also includes several base <emphasis>jar</emphasis> files.</para>
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75 |
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76 | <para>To start, we set up a binary installation of the JDK created
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77 | by the BLFS editors. It is installed in the <filename>/opt</filename>
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78 | directory to allow for multiple installations, including a source based
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79 | version.</para>
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80 |
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81 | <bridgehead renderas="sect3">Binary Package Information</bridgehead>
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82 | <itemizedlist spacing="compact">
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83 | <listitem>
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84 | <para>Binary download (x86):
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85 | <ulink url="&openjdk-download-binary-x86;"/></para>
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86 | </listitem>
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87 | <listitem>
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88 | <para>Download MD5 sum: &openjdk-bin-md5sum-x86;</para>
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89 | </listitem>
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90 | <listitem>
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91 | <para>Download size (binary): &openjdk-bin-size-x86;</para>
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92 | </listitem>
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93 | <listitem>
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94 | <para>Estimated disk space required: &openjdk-bin-buildsize-x86;</para>
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95 | </listitem>
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96 | </itemizedlist>
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97 | <itemizedlist spacing="compact">
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98 | <listitem>
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99 | <para>Binary download (x86_64):
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100 | <ulink url="&openjdk-download-binary-x64;"/></para>
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101 | </listitem>
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102 | <listitem>
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103 | <para>Download MD5 sum: &openjdk-bin-md5sum-x64;</para>
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104 | </listitem>
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105 | <listitem>
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106 | <para>Download size (binary): &openjdk-bin-size-x64;</para>
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107 | </listitem>
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108 | <listitem>
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109 | <para>Estimated disk space required: &openjdk-bin-buildsize-x64;</para>
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110 | </listitem>
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111 | </itemizedlist>
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112 |
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113 | <para>Begin by extracting the appropriate binary tarball for your
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114 | architecture and changing to the extracted directory. Install the binary
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115 | <application>OpenJDK</application> with the following commands as the
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116 | <systemitem class="username">root</systemitem> user:</para>
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117 |
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118 | <screen role="root"><userinput>install -vdm755 /opt/OpenJDK-&openjdk-version;-bin &&
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119 | mv -v * /opt/OpenJDK-&openjdk-version;-bin &&
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120 | chown -R root:root /opt/OpenJDK-&openjdk-version;-bin</userinput></screen>
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121 |
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122 | <para>Configure the temporary <application>OpenJDK</application>
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123 | installation with the following commands:</para>
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124 |
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125 | <screen><userinput>export CLASSPATH=.:/usr/share/java &&
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126 | export PATH="$PATH:/opt/OpenJDK-&openjdk-version;-bin/bin"</userinput></screen>
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127 |
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128 | <para>The binary version is now installed. If you don't want to compile the
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129 | sources, skip ahead to the <xref linkend='openjdk-config'/> section.
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130 | Otherwise, continue to the <xref linkend='junit'/>, <xref
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131 | linkend='apache-ant'/>, and <xref linkend='openjdk'/> sections.</para>
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132 |
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133 | </sect2>
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134 |
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135 | </sect1>
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