openbook.util

Class PropertyHelper

java.lang.Object

openbook.util.PropertyHelper

public class PropertyHelper
extends Object

A set of static utility functions to read properties from file, manage properties with multi-part keys, array style properties etc.

Author:

Pinaki Poddar

Constructor Summary

Constructors

Constructor and Description
PropertyHelper()

Method Summary

Modifier and Type	Method and Description
static boolean	canFind(String resource) Affirm if the given resource is available either as a resource in the current thread's context classpath or as a file.
static Map<String,Object>	filter(Map<String,Object> props, String name, boolean prefix, boolean includeArrays) Filter the properties by the given name.
static Map<String,List<Object>>	filterArrayKeys(Map<String,Object> props, String name, boolean prefix) Select only those property keys which ends with an array marker such as openjpa.DataCache[1].
static double	getDouble(Map<String,Object> props, String key, double def)
static int	getInteger(Map<String,Object> props, String key, int def)
static Map<String,String>	getMap(Map<String,Object> props, String key)
static Map<String,String>	getMap(Map<String,Object> props, String key, Map<String,String> def)
static String	getPrefix(String s)
static Map<String,Object>	getSection(Map<String,Object> props, String section) Get the portion of the given map whose key has the given section at prefix.
static Map<String,Object>	getSection(Map<String,Object> props, String section, boolean retain) Get the portion of the given map whose key has the given section at prefix.
static String	getString(Map<String,Object> props, String key, String def)
static List<String>	getStringList(Map<String,Object> props, String key)
static List<String>	getStringList(Map<String,Object> props, String key, List<String> def)
static Set<String>	getSubsectionKeys(Set<String> keys, String section)
static Map<String,Object>	load(String resource) Load properties from the given name resource.
static Map<String,Object>	overwriteWithSystemProperties(Map<String,Object> original) Overwrites any key-value pair in the given map for which a System property is available
static Map<String,Object>	toMap(Properties p)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PropertyHelper

public PropertyHelper()

Method Detail

filter

public static Map<String,Object> filter(Map<String,Object> props,
                                        String name,
                                        boolean prefix,
                                        boolean includeArrays)

Filter the properties by the given name.

Parameters:

name - a part of the key

prefix - if true, property key must begin with the given name. Otherwise, the key merely contains the name to qualify.

Returns:

key-value pairs that match.

filterArrayKeys

public static Map<String,List<Object>> filterArrayKeys(Map<String,Object> props,
                                                       String name,
                                                       boolean prefix)

Select only those property keys which ends with an array marker such as openjpa.DataCache[1]. The multiple values of the property is inserted into the resultant map as a List of object against the original key.
For example, if the original map had three key-value pairs as

openjpa.DataCache[1]=true openjpa.DataCache[2]=false openjpa.DataCache[3]=default
Then that will result into a single entry in the resultant Map under the key openjpa.DataCache with a value as a List of three elements namely {true, false, default}. The array index values are not significant other than they must all be different for the same base key.

Parameters:

name - part of the property key

prefix - does the name must appear as a prefix?

Returns:

key-value pairs that match.

load

public static Map<String,Object> load(String resource)

Load properties from the given name resource. The given named resource is first looked up as resource on the current thread's context and if not found as a file input.

Parameters:

resource - name a of resource.

Returns:

empty properties if no resource found.

canFind

public static boolean canFind(String resource)

Affirm if the given resource is available either as a resource in the current thread's context classpath or as a file.

toMap

public static Map<String,Object> toMap(Properties p)

overwriteWithSystemProperties

public static Map<String,Object> overwriteWithSystemProperties(Map<String,Object> original)

Overwrites any key-value pair in the given map for which a System property is available

Parameters:

original - properties to be overwritten

Returns:

the original property overwritten with System properties

getInteger

public static int getInteger(Map<String,Object> props,
                             String key,
                             int def)

getDouble

public static double getDouble(Map<String,Object> props,
                               String key,
                               double def)

getString

public static String getString(Map<String,Object> props,
                               String key,
                               String def)

getStringList

public static List<String> getStringList(Map<String,Object> props,
                                         String key)

getStringList

public static List<String> getStringList(Map<String,Object> props,
                                         String key,
                                         List<String> def)

getMap

public static Map<String,String> getMap(Map<String,Object> props,
                                        String key)

getMap

public static Map<String,String> getMap(Map<String,Object> props,
                                        String key,
                                        Map<String,String> def)

getSubsectionKeys

public static Set<String> getSubsectionKeys(Set<String> keys,
                                            String section)

getPrefix

public static String getPrefix(String s)

getSection

public static Map<String,Object> getSection(Map<String,Object> props,
                                            String section)

Get the portion of the given map whose key has the given section at prefix.

Parameters:

props - a set of name-value pair

section - a string representing section of a key

Returns:

a new map with only the keys that starts with the given section.

getSection

public static Map<String,Object> getSection(Map<String,Object> props,
                                            String section,
                                            boolean retain)

Get the portion of the given map whose key has the given section at prefix.

Parameters:

props - a set of name-value pair

section - a string representing section of a key

retain - if true the key of resultant map is same as the original map. Otherwise the resultant map keys are without the section prefix.

Returns:

the map with only the keys that starts with the given section.