This Refcard will help Java developers working with multi-threaded programs to understand core concurrency concepts and how to apply them. Overview the. This Refcard covers JVM internals, class loading (updated to reflect the new Metaspace in Java 8), garbage collection, troubleshooting, monitoring, concurrency. This Refcard focuses on the design, deployment, service discovery, and management of Java applications on the open-source project called Docker so that you.
| Author: | Gardarn Malakazahn |
| Country: | Monaco |
| Language: | English (Spanish) |
| Genre: | Marketing |
| Published (Last): | 5 September 2012 |
| Pages: | 269 |
| PDF File Size: | 3.1 Mb |
| ePub File Size: | 3.13 Mb |
| ISBN: | 714-3-96439-655-3 |
| Downloads: | 23231 |
| Price: | Free* [*Free Regsitration Required] |
| Uploader: | Yozshutilar |
Gives you an overview of key aspects refcad the Java language and references on the core library, commonly used tools, and Java 8 features. This Refcard gives you an overview of key aspects of the Java language and cheat sheets on the core library formatted output, collections, regular expressions, logging, properties as well as the most commonly used tools javac, java, jar. Lambda expressions represent anonymous functions. You can pass javs as method parameters or return them.
Java Performance Optimization
The same can jvaa done with named methods using method references. Each format specifier has the following form. See the tables for flags and conversion characters.
Another file can be specified with the system property java. Note that the LogManager runs before main. Sets the class path, used to search for class files. See the previous table for details. Note that javac can succeed when java javs if the current directory is on the source path but not the class path. When this option is used, the class path is ignored. Sets the initial or maximum heap size. The size is a value in bytes. Add a suffix k or m for kilobytes or megabytes, for example, -Xmx10m.
Over a million developers have joined DZone. Refcard Core Java. A Power-User’s Guide to Java Gives you an overview of key aspects of the Java language and references on the core library, commonly used tools, and Java 8 features.
Core Java Reference Card
PDF for easy Reference. In the “generalized” for loop, the expression after the: If you omit a break, processing continues with the next case. Operators with the kava precedence Notes []. The right hand side is reduced modulo 32 if the left hand side is an int or modulo 64 if the left hand side is a long. Type Size Range Notes int 4 bytes -2,, to 2,, just over 2 billion The wrapper type is Integer.
Use BigInteger for arbitrary precision integers short 2 bytesto 32, long refcars bytes -9,,, to 9,,, Literals end with L e. Functional Interfaces Interfaces with a single abstract method. Typical usage of method references: The remove method removes the element returned by the preceding call to next strs. Use a TreeMap to traverse in sort order requires that key type is comparable for Map.
Here we replace all digit sequences with a. Here we find the hours and minutes in a date. Any of the characters represented by C1C2. The Ci are characters, character ranges c1-c2, or character classes.
Characters not represented by any of C1C2. Characters represented by all of C1C2.
See the table below for the naming pattern. Configuration Property Description Default loggerName. An instance is created for each class name, using the default constructor java.
SimpleFormatter for ConsoleHandler java. The following tokens are replaced when the file is created: If any of the specified file names are directories, the jar program processes them recursively C Temporarily changes the directory. For example, jar cvfC myprog. If this parameter is missing, jar will write the result to standard output when creating a JAR file or read it from standard input when extracting or tabulating a JAR file i Creates an index file for speeding up lookups in a large archive m Adds a manifest to the JAR file.
If you supply one or more file names, only those files are extracted. Otherwise, all files are extracted. Option Purpose -cp or -classpath Sets the class path, used to search for class files. The latter refers to all JAR files in the given directory. Class path items are separated by: Unix or ; Windows. If no class path is specified, it is set to the current directory.
If a class path is specified, the current directory is not automatically included-add a. If source and class files are present for a given file, the source is compiled if it is newer. If no source path is specified, it is set to the current directory -d Sets the path used to place the class files.
Use this option to separate. Valid values are 1. By default, assertions are disabled. This option may be useful to debug class loading problems. Option Description -cp or -classpath Sets the class path, used to search for class files. Note that javac can succeed when java fails if the current directory is on the source path but not the class path -ea or -enableassertions Enable assertions.
When this option is used, the class path is ignored -verbose Shows the classes that are loaded. This option may be useful to debug class loading problems -Xms size -Xmx size Sets the initial or maximum heap size. Support for JavaBeans components classes with properties and event listeners.
Utilities including data structures, concurrency, regular expressions, and logging. The wrapper type is Integer. Use BigInteger for arbitrary precision integers.
The wrapper type is Character. An ordered sequence that allows efficient insertions and removal at any location. A map with values that can be reclaimed by the garbage collector if they are not used elsewhere. Remove elements that match a condition.
The remove method removes the element returned by the preceding call to next. Add all strings from an array of strings. Insert or remove an element at a specified index, shifting the elements with higher index values.
Convert from array to list. Use the varargs form to make a small collection. Sort a list by the natural order of the elements, or with a custom comparator. Make a map that is traversed in insertion order requires hashCode for key type. Use a TreeMap to traverse in sort order requires that key type is comparable. List of choices, separated by. Find all groups indicated by parentheses in the pattern. The control characters tab, newline, return, form feed, alert, and escape.
Block is the name of a Unicode character block, with spaces removed, such as BasicLatin or Mongolian. Category is the name of a Unicode character category such as L letter or Sc currency symbol.
Match characters independently of the letter case.
When using this flag, the. Takes canonical equivalence of Unicode characters into account. The input string that specifies the pattern is treated as a sequence of literal characters, without special meanings for. Logs a message of level FINE.
Sets the logging level to FINE. By default, the logging level is INFO, and less severe logging messages are not logged. Adds a file handler for saving the log records in a file. This handler uses a simple formatter instead of the XML formatter that is the default for file handlers.
A whitespace or comma-separated list of class names for the root logger. An instance is created for each class name, using the default constructor. A whitespace or comma-separated list of class names for the given logger. The default naming pattern for log files. The default append mode for file loggers; true to append to an existing log file. Creates a new or empty archive and adds files to it. If any of the specified file names are directories, the jar program processes them recursively.