Essential Books

Getting sub-nodes of Preferences

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Preferences objects always represent a specific node in a whole Preferences tree, kind of like this: 

/userRoot
├── com
│   └── mycompany
│       └── myapp
│           ├── darkApplicationMode=true
│           ├── showExitConfirmation=false
│           └── windowMaximized=true
└── org
```
└── myorganization
    └── anotherapp
        ├── defaultFont=Helvetica
        ├── defaultSavePath=/home/matt/Documents
        └── exporting
            ├── defaultFormat=pdf
            └── openInBrowserAfterExport=false
To select the `/com/mycompany/myapp` node:

1. By convention, based on the package of a class:

package com.mycompany.myapp;

// …

// Because this class is in the com.mycompany.myapp package, the node // /com/mycompany/myapp will be returned. Preferences myApp = Preferences.userNodeForPackage(getClass()); 

2. By relative path:

       Preferences myApp = Preferences.userRoot().node("com/mycompany/myapp");

   Using a relative path (a path not starting with a `/`) will cause the path to be resolved relative to the parent node it is resolved on. For example, the following example will return the node of the path `/one/two/three/com/mycompany/myapp`:

Preferences prefix = Preferences.userRoot().node(“one/two/three”); Preferences myAppWithPrefix = prefix.node(“com/mycompany/myapp”); // prefix is /one/two/three // myAppWithPrefix is /one/two/three/com/mycompany/myapp 

3. By absolute path:

       Preferences myApp = Preferences.userRoot().node("/com/mycompany/myapp");

   Using an absolute path on the root node will not be different from using a relative path. The difference is that, if called on a sub-node, the path will be resolved relative to the root node.

Preferences prefix = Preferences.userRoot().node(“one/two/three”); Preferences myAppWitoutPrefix = prefix.node(”/com/mycompany/myapp”); // prefix is /one/two/three // myAppWitoutPrefix is /com/mycompany/myapp

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Preferences:
* Preferences
* Using preferences
* Adding event listeners
* Getting sub-nodes of Preferences
* Exporting preferences
* Importing preferences
* Removing event listeners
* Coordinating preferences access across multiple application instances
* Getting preferences values
* Setting preferences values
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0 Inheritance
1 Getting started with Java
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38 Iterator and Iterable
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84 The Classpath
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90 XML XPath Evaluation
91 Performance Tuning
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93 Common Pitfalls
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95 Java Compiler
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100 Dates and Time using java.time
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103 Just in Time JIT compiler
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118 Pitfalls - threads and concurrency
119 Splitting a string into fixed length parts
120 Pitfalls - nulls and NullPointerException
121 SecurityManager
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124 java.util.Objects class
125 Java command: java and javaw
126 Atomic types
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129 sun.misc.Unsafe
130 Java Memory Model
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137 Java Virtual Machine JVM
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142 Java SE 8 Features
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147 Using ThreadPoolExecutor in multi-threaded applications
148 Java Editions, versions, releases and distributions
149 Dynamic method dispatch
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152 Generating Java Code
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176 Enum starting with a number
177 SortedMap
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180 StringBuffer
181 Choosing Collections
182 C++ Comparison
183 CompletableFuture
184 Contributors