com.github.drinkjava2.jdbpro.template
Class BasicSqlTemplate

java.lang.Object
  com.github.drinkjava2.jdbpro.template.BasicSqlTemplate

All Implemented Interfaces:

SqlTemplateEngine

public class BasicSqlTemplate
extends Object
implements SqlTemplateEngine

BasicSqlTemplate is a simple implementation of SqlTemplateEngine. It allow use #{xxxx} format parameters in template, and replace ${xxxx} pieces directly. This is a thread safe class.

Since:

1.7.0

Author:

Yong Zhu

Nested Class Summary

static class

BasicSqlTemplate.BasicSqlTemplateException

Field Summary

protected Boolean	allowColonAsDelimiter If set true, ${placeHolder} can write as :placeHolder Default is true
protected Boolean	dollarKeyForDollarPlaceHolder If set true, for ${placeHolder} in template, should use put("$placeHolder",value) instead of use put("placeHolder",value) Default is false

Constructor Summary

BasicSqlTemplate()
Build a BasicSqlTemplate instance, default use #{} as delimiter, dollarKeyForDollarPlaceHolder is false, allow

BasicSqlTemplate(String startDelimiter, String endDelimiter, Boolean allowColonAsDelimiter, Boolean dollarKeyForDollarPlaceHolder)

Method Summary

static BasicSqlTemplate	instance()
static boolean	isEmpty(CharSequence cs) Checks if a CharSequence is empty ("") or null.
PreparedSQL	render(String sqlTemplate, Map<String,Object> paramMap, Object[] unbindParams) Render a SQL Template String and a Map instance into a PreparedSQL instance
static String	substringAfter(String str, String separator) Gets the substring after the first occurrence of a separator.
static String	substringBefore(String str, String separator) Gets the substring before the first occurrence of a separator.

Methods inherited from class java.lang.Object

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

Field Detail

dollarKeyForDollarPlaceHolder

protected Boolean dollarKeyForDollarPlaceHolder

If set true, for ${placeHolder} in template, should use put("$placeHolder",value) instead of use put("placeHolder",value)
Default is false

allowColonAsDelimiter

protected Boolean allowColonAsDelimiter

If set true, ${placeHolder} can write as :placeHolder
Default is true

Constructor Detail

BasicSqlTemplate

public BasicSqlTemplate()

Build a BasicSqlTemplate instance, default use #{} as delimiter, dollarKeyForDollarPlaceHolder is false, allow

BasicSqlTemplate

public BasicSqlTemplate(String startDelimiter,
                        String endDelimiter,
                        Boolean allowColonAsDelimiter,
                        Boolean dollarKeyForDollarPlaceHolder)

Parameters:

startDelimiter - The start delimiter

endDelimiter - The end delimiter

allowColonAsDelimiter - If set true, write :placeHolder is equal to #{placeHolder}

dollarKeyForDollarPlaceHolder - If set true, ${placeHolder} should use put("$placeHolder",value) instead of use put("placeHolder",value)

Method Detail

instance

public static BasicSqlTemplate instance()

Returns:

A singleton instance of BasicSqlTemplate

render

public PreparedSQL render(String sqlTemplate,
                          Map<String,Object> paramMap,
                          Object[] unbindParams)

Description copied from interface: SqlTemplateEngine

Render a SQL Template String and a Map instance into a PreparedSQL instance

Specified by:

render in interface SqlTemplateEngine

Parameters:

sqlTemplate - A SQL Template String, or a SqlId used to locate the real SQL template String

paramMap - A Map instance, key is String type, value is Object type

unbindParams - Optional, some time un-binded parameter can make template SQL executed like normal SQL, i.e., use normal params to replace placeholder according apperance order

            For example: 
            Template "delete from #{tb}", use put("tb","users") method,      will get "delete from ?"
            Template "delete from ${tb}", use replace("tb","users") method,   will get "delete from users"
            Template "delete from #{tb}", use replace("tb","users") method,   will cause an Exception
            Template "delete from ${tb}", use put("tb","users") method,      will cause an Exception
 
            

This design is to avoid typing mistake cause a SQL injection security leak, when programmer use replace() or replace0() method, he will aware this is a String direct replace method, not a SQL parameter, SQL parameter always use "put" method.

Returns:

PreparedSQL instance

isEmpty

public static boolean isEmpty(CharSequence cs)

Checks if a CharSequence is empty ("") or null.

 StringUtils.isEmpty(null)      = true
 StringUtils.isEmpty("")        = true
 StringUtils.isEmpty(" ")       = false
 StringUtils.isEmpty("bob")     = false
 StringUtils.isEmpty("  bob  ") = false
 

NOTE: This method changed in Lang version 2.0. It no longer trims the CharSequence. That functionality is available in isBlank().

Parameters:

cs - the CharSequence to check, may be null

Returns:

true if the CharSequence is empty or null

substringBefore

public static String substringBefore(String str,
                                     String separator)

Gets the substring before the first occurrence of a separator. The separator is not returned.

A null string input will return null. An empty ("") string input will return the empty string. A null separator will return the input string.

If nothing is found, the string input is returned.

 StringUtils.substringBefore(null, *)      = null
 StringUtils.substringBefore("", *)        = ""
 StringUtils.substringBefore("abc", "a")   = ""
 StringUtils.substringBefore("abcba", "b") = "a"
 StringUtils.substringBefore("abc", "c")   = "ab"
 StringUtils.substringBefore("abc", "d")   = "abc"
 StringUtils.substringBefore("abc", "")    = ""
 StringUtils.substringBefore("abc", null)  = "abc"
 

Parameters:

str - the String to get a substring from, may be null

separator - the String to search for, may be null

Returns:

the substring before the first occurrence of the separator, null if null String input

substringAfter

public static String substringAfter(String str,
                                    String separator)

Gets the substring after the first occurrence of a separator. The separator is not returned.

A null string input will return null. An empty ("") string input will return the empty string. A null separator will return the empty string if the input string is not null.

If nothing is found, the empty string is returned.

 StringUtils.substringAfter(null, *)      = null
 StringUtils.substringAfter("", *)        = ""
 StringUtils.substringAfter(*, null)      = ""
 StringUtils.substringAfter("abc", "a")   = "bc"
 StringUtils.substringAfter("abcba", "b") = "cba"
 StringUtils.substringAfter("abc", "c")   = ""
 StringUtils.substringAfter("abc", "d")   = ""
 StringUtils.substringAfter("abc", "")    = "abc"
 

Parameters:

str - the String to get a substring from, may be null

separator - the String to search for, may be null

Returns:

the substring after the first occurrence of the separator, null if null String input