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Table of Contents

Preface	1
Chapter 1: Getting Started with Groovy	7
Introduction	7
Installing Groovy on Windows	8
Installing Groovy on Linux and OS X	10
Executing Groovy code from the command line	11
Using Groovy as a command-line text file editor	14
Using Groovy to start a server on the command line	16
Running Groovy with invokedynamic support	17
Building Groovy from source	18
Managing multiple Groovy installations on Linux	20
Using groovysh to try out Groovy commands	23
Starting groovyConsole to execute Groovy snippets	29
Configuring Groovy in Eclipse	35
Configuring Groovy in IntelliJ IDEA	42
Chapter 2: Using Groovy Ecosystem	47
Introduction	47
Using Java classes from Groovy	48
Embedding Groovy into Java	51
Compiling Groovy code	57
Simplifying dependency management with Grape	60
Integrating Groovy into the build process using Ant	63
Integrating Groovy into the build process using Maven	71
Integrating Groovy into the build process using Gradle	75
Generating documentation for Groovy code	78
Checking Groovy code's quality with CodeNarc	82

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Table of Contents

Chapter 3: Using Groovy Language Features	89
Introduction	89
Searching strings with regular expressions	90
Writing less verbose Java Beans with Groovy Beans	92
Inheriting constructors in Groovy classes	99
Adding the cloning functionality to Groovy Beans	100
Defining code as data in Groovy	104
Defining data structures as code in Groovy	108
Implementing multiple inheritance in Groovy	117
Adding a functionality to the existing Java/Groovy classes	123
Defining type-checking rules for dynamic code	126
Adding automatic logging to Groovy classes	132

Chapter 4: Working with Files in Groovy	135
Introduction	136
Reading from a file	136
Reading a text file line by line	138
Processing every word in a text file	140
Writing to a file	142
Replacing tabs with spaces in a text file	144
Filtering a text file's content	146
Deleting a file or directory	149
Walking through a directory recursively	151
Searching for files	153
Changing file attributes on Windows	157
Reading data from a ZIP file	159
Reading an Excel file	160
Extracting data from a PDF	162

Chapter 5: Working with XML in Groovy	167
Introduction	167
Reading XML using XmlSlurper	168
Reading XML using XmlParser	170
Reading XML content with namespaces	172
Searching in XML with GPath	175
Searching in XML with XPath	178
Constructing XML content	184
Modifying XML content	187
Sorting XML nodes	189
Serializing Groovy Beans to XML	192

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	Table of Contents
Chapter 6: Working with JSON in Groovy	197
Introduction	197
Parsing JSON messages with JsonSlurper	198
Constructing JSON messages with JsonBuilder	201
Modifying JSON messages	204
Validating JSON messages	205
Converting JSON message to XML	211
Converting JSON message to Groovy Bean	214
Using JSON to configure your scripts	218
Chapter 7: Working with Databases in Groovy	223
Introduction	223
Creating a database table	224
Connecting to an SQL database	228
Querying an SQL database	231
Modifying data in an SQL database	235
Calling a stored procedure	239
Reading BLOB/CLOB from a database	242
Building a simple ORM framework	244
Using Groovy to access Redis	246
Using Groovy to access MongoDB	252
Using Groovy to access Apache Cassandra	256
Chapter 8: Working with Web Services in Groovy	263
Introduction	263
Downloading content from the Internet	264
Executing an HTTP GET request	265
Executing an HTTP POST request	268
Constructing and modifying complex URLs	271
Issuing a REST request and parsing a response	272
Issuing a SOAP request and parsing a response	276
Consuming RSS and Atom feeds	279
Using basic authentication for web service security	283
Using OAuth for web service security	284
Chapter 9: Metaprogramming and DSLs in Groovy	289
Introduction	289
Querying methods and properties	290
Dynamically extending classes with new methods	293
Overriding methods dynamically	296
Adding performance logging to methods	299

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Table of Contents
Adding a caching functionality around methods		305
Adding transparent imports to a script		317
DSL for executing commands over SSH		319
DSL for generating reports from logfiles		327
Chapter 10: Concurrent Programming in Groovy		335
Introduction		335
Processing collections concurrently		336
Downloading files concurrently		340
Splitting a large task into smaller parallel jobs		344
Running tasks in parallel and asynchronously		349
Using actors to build message-based concurrency		355
Using STM to atomically update fields		361
Using dataflow variables for lazy evaluation		365
Index		371

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