Implement substring search feature

docs/UserGuide.md

@@ -250,14 +250,16 @@ Example: `asset old/hammer new/screwdriver` edits the asset `hammer`, changing i
 
 ### Finding Contacts: `find`
 
-Finds contacts whose names, tags or assets contain any of the given keywords.
+Finds contacts by names, tags or assets.
 
-Format: `find KEYWORD [KEYWORD]...`
+Format: `find QUERY`
 
-Example: `find John` searches all contact names, tags and assets for the keyword `John`.
+Example: `find John` searches all contact names, tags and assets for the query `John`.
 
-* At least one keyword must be provided.
-* Keywords are case-insensitive.
+* The query is case-insensitive.
+* All whitespaces in both the query and fields will be ignored.
+* Each field is individually checked against the query.
+* A match is found if the query is a substring of the field being checked.
 
 --------------------------------------------------------------------------------------------------------------------
 
@@ -326,15 +328,15 @@ Furthermore, certain edits can cause the AssetBook-3 to behave in unexpected way
 
 ## Command summary
 
-Action           | Format                                                                        | Example
------------------|-------------------------------------------------------------------------------|--- 
-**Add**          | `add n/NAME p/PHONE e/EMAIL o/OFFICE [t/TAG]... [a/ASSET]...`                 | `add n/John Doe e/johndoe@example.com p/+12345678 a/L293D`
-**Delete**       | `delete INDEX`                                                                | `delete 1`
-**Edit contact** | `edit INDEX [n/NAME] [p/PHONE] [e/EMAIL] [o/OFFICE] [t/TAG]... [a/ASSET]...`  | `edit 1 e/newemail@example.com`
-**Edit asset**   | `asset old/OLD_ASSET_NAME new/NEW_ASSET_NAME`                                 | `asset old/hammer new/screwdriver`
-**Find**         | `find KEYWORD [KEYWORD]...`                                                   | `find John`
-**Undo**         | `undo`                                                                        | `undo`
-**Exit**         | `exit`                                                                        | `exit`
+Action           | Format                                                                       | Example
+-----------------|------------------------------------------------------------------------------|--- 
+**Add**          | `add n/NAME p/PHONE e/EMAIL o/OFFICE [t/TAG]... [a/ASSET]...`                | `add n/John Doe e/johndoe@example.com p/+12345678 a/L293D`
+**Delete**       | `delete INDEX`                                                               | `delete 1`
+**Edit contact** | `edit INDEX [n/NAME] [p/PHONE] [e/EMAIL] [o/OFFICE] [t/TAG]... [a/ASSET]...` | `edit 1 e/newemail@example.com`
+**Edit asset**   | `asset old/OLD_ASSET_NAME new/NEW_ASSET_NAME`                                | `asset old/hammer new/screwdriver`
+**Find**         | `find QUERY`                                                                 | `find John`
+**Undo**         | `undo`                                                                       | `undo`
+**Exit**         | `exit`                                                                       | `exit`
 
 ---{.double}
 

src/main/java/seedu/address/logic/commands/FindCommand.java

@@ -3,30 +3,31 @@
 import static java.util.Objects.requireNonNull;
 import static seedu.address.logic.Messages.MESSAGE_INVALID_COMMAND_FORMAT;
 
-import java.util.Arrays;
+import java.util.function.Predicate;
 
-import seedu.address.commons.util.ToStringBuilder;
 import seedu.address.logic.Messages;
 import seedu.address.model.Model;
-import seedu.address.model.person.PersonMatchesKeywordsPredicate;
+import seedu.address.model.person.Person;
+import seedu.address.model.person.PersonMatchesQueryPredicate;
 
 /**
- * Finds and lists all persons in address book whose name contains any of the argument keywords.
- * Keyword matching is case insensitive.
+ * Finds and lists all persons in the address book such that certain fields match the predicate.
+ * See {@code PersonMatchesQueryPredicate}.
  */
 public class FindCommand extends Command {
 
     public static final String COMMAND_WORD = "find";
 
     public static final String MESSAGE_USAGE = COMMAND_WORD
-            + ": Finds all persons whose names, assets or tags contain any of "
-            + "the specified keywords (case-insensitive) and displays them as a list with index numbers.\n"
-            + "Parameters: KEYWORD [MORE_KEYWORDS]...\n"
-            + "Example: " + COMMAND_WORD + " alice bob charlie";
+            + ": Finds all persons whose names, assets or tags contains "
+            + "the specified query (case-insensitive) and displays them as a list with index numbers.\n"
+            + "All whitespaces are ignored.\n"
+            + "Parameters: QUERY\n"
+            + "Example: " + COMMAND_WORD + " alex";
 
-    private final PersonMatchesKeywordsPredicate predicate;
+    private final Predicate<Person> predicate;
 
-    public FindCommand(PersonMatchesKeywordsPredicate predicate) {
+    public FindCommand(Predicate<Person> predicate) {
         this.predicate = predicate;
     }
 
@@ -49,9 +50,7 @@ public static FindCommand of(String args) throws IllegalArgumentException {
                     String.format(MESSAGE_INVALID_COMMAND_FORMAT, FindCommand.MESSAGE_USAGE));
         }
 
-        String[] nameKeywords = trimmedArgs.split("\\s+");
-
-        return new FindCommand(new PersonMatchesKeywordsPredicate(Arrays.asList(nameKeywords)));
+        return new FindCommand(new PersonMatchesQueryPredicate(trimmedArgs));
     }
 
     @Override
@@ -69,11 +68,4 @@ public boolean equals(Object other) {
         return predicate.equals(otherFindCommand.predicate);
     }
 
-    @Override
-    public String toString() {
-        return new ToStringBuilder(this)
-                .add("predicate", predicate)
-                .toString();
-    }
-
 }

src/main/java/seedu/address/model/person/PersonMatchesQueryPredicate.java

@@ -0,0 +1,67 @@
+package seedu.address.model.person;
+
+import static java.util.Objects.requireNonNull;
+
+import java.util.function.Predicate;
+
+/**
+ * Tests that a {@code Person}'s {@code Name}, {@code Tags} or {@code Assets} matches the search query.
+ * The algorithm removes all whitespaces and checks if the query is a substring of a field.
+ * The substring matching is case-insensitive.
+ */
+public class PersonMatchesQueryPredicate implements Predicate<Person> {
+
+    private static final String STRIP_WHITESPACE_REGEX = "\\s+";
+    private static final String EMPTY_STRING = "";
+
+    private final String query;
+
+    /**
+     * Processes the query string and constructs the object.
+     * @param query the query string.
+     * @throws NullPointerException if the query string is null.
+     * @throws AssertionError if the query string is empty.
+     */
+    public PersonMatchesQueryPredicate(String query) {
+        requireNonNull(query);
+        assert !query.isEmpty();
+        this.query = processString(query);
+    }
+
+    private static String processString(String str) {
+        return str.toLowerCase().replaceAll(STRIP_WHITESPACE_REGEX, EMPTY_STRING);
+    }
+
+    //@@author rizkidelta
+    @Override
+    public boolean test(Person person) {
+        return doesStringMatchQuery(person.getName().toString(), query)
+               || person.getTags().stream().anyMatch(tag -> doesStringMatchQuery(tag.get(), query)
+               || person.getAssets().stream().anyMatch(asset -> doesStringMatchQuery(asset.get(), query)));
+    }
+
+    //@@author rizkidelta
+    private static boolean doesStringMatchQuery(String text, String query) {
+        requireNonNull(text);
+
+        // only need to process text, as query is already processed in the constructor
+        text = processString(text);
+        return text.contains(query);
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other == this) {
+            return true;
+        }
+
+        // instanceof handles nulls
+        if (!(other instanceof PersonMatchesQueryPredicate)) {
+            return false;
+        }
+
+        PersonMatchesQueryPredicate otherPersonMatchesQueryPredicate = (PersonMatchesQueryPredicate) other;
+        return query.equals(otherPersonMatchesQueryPredicate.query);
+    }
+
+}

src/main/java/seedu/address/model/tag/Tag.java

@@ -7,7 +7,7 @@
 
 /**
  * Represents a Tag in the address book.
- * Guarantees: immutable; name is valid as declared in {@link #isValidTagName(String)}
+ * Guarantees: immutable; name is valid as declared in {@link #isValid(String)}
  */
 public class Tag {
 

src/test/java/seedu/address/logic/commands/CommandTestUtil.java

@@ -11,15 +11,14 @@
 import static seedu.address.testutil.Assert.assertThrows;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 
 import seedu.address.commons.core.index.Index;
 import seedu.address.logic.commands.exceptions.CommandException;
 import seedu.address.model.AddressBook;
 import seedu.address.model.Model;
 import seedu.address.model.person.Person;
-import seedu.address.model.person.PersonMatchesKeywordsPredicate;
+import seedu.address.model.person.PersonMatchesQueryPredicate;
 import seedu.address.testutil.EditPersonDescriptorBuilder;
 
 /**
@@ -118,7 +117,7 @@ public static void showPersonAtIndex(Model model, Index targetIndex) {
 
         Person person = model.getFilteredPersonList().get(targetIndex.getZeroBased());
         final String[] splitName = person.getName().toString().split("\\s+");
-        model.updateFilteredPersonList(new PersonMatchesKeywordsPredicate(Arrays.asList(splitName[0])));
+        model.updateFilteredPersonList(new PersonMatchesQueryPredicate(splitName[0]));
 
         assertEquals(1, model.getFilteredPersonList().size());
     }