16f6c0aecf
Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in.
89 lines
1.9 KiB
Plaintext
89 lines
1.9 KiB
Plaintext
== Why is this an issue?
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``++transient++`` fields are ignored by Java's automatic serizalization mechanisms, which means that when a object is deserialized, those fields will be set to their default values.
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``++transient++`` fields that are referenced in multiple places in a class seem to play a significant role in that class. Allowing such significant fields to be left in a default state after deserialization may not be the best course, so they should probably be set in either a ``++readObject()++`` or ``++readResolve()++`` method.
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=== Noncompliant code example
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Using the default threshold of 3:
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[source,java]
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----
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class Fruit implements Serializable {
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private transient Seed seed;
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public Fruit (Seed seed) {
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this.seed = seed; // 1st set
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}
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public void setSeed (Seed seed) {
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this.seed = seed; // 2nd set
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}
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public Seed getSeed() {
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return seed; // not counted; read, not write.
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}
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public void sprout () {
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this.seed = new GerminatedSeed(); // Noncompliant; 3rd write
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//...
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}
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}
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----
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=== Compliant solution
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[source,java]
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----
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class Fruit implements Serializable {
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private transient Seed seed;
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public Fruit (Seed seed) {
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this.seed = seed; // 1st reference
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}
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public void setSeed (Seed seed)
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this.seed = seed; // 2nd reference
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}
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public Seed getSeed() {
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return seed; // not counted; read, not write.
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}
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public void sprout () {
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this.seed = new GerminatedSeed(); // Noncompliant; 3rd write
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//...
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}
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protected Object readResolve() throws ObjectStreamException {
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// ...
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}
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}
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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* Set "xxx" in "readObject()" or "readResolve()".
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=== Parameters
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.threshold
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****
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----
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3
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----
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The number of times a transient field is set that indicates it should be restored during deserialization.
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****
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endif::env-github,rspecator-view[]
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